Friday, January 12, 2018

Magic wand to make stinky water clean: Japanese first modern waterworks

Before visiting the largest “Citizen” Forest of Yokohama, let’s talk again about 4 large water reservoirs for Kanagawa Prefecture. The line-up is

Name of the Dam
Accompanying Lake
Operational since
Water Storage Volume (million m3)
Catchment Area (km2)
Sagami Dam
Lake Sagami
Shiroyama Dam
Lake Tsukui
Miho Dam
Lake Tanzawa
Miyagase Dam
Lake Miyagase

These dams (plus one more that I tell you next week) provide 90% of tap water in Kanagawa. The remaining 10% is for Hadano City 秦野市 and the surrounding area who uses underground water system of Mizunashi River 水無川 from Tanzawa. Unlike Tokyo, Kanagawa Prefecture procures all the water within its border. Water source forests in western Kanagawa receive lots of rain so that Kanagawa seldom has water shortage. Moreover, Kanagawa Water Source Authority神奈川県内広域水道企業団 and Waterworks Bureaus of cities have an impressive network to smooth out water supply for the entire prefecture. The dams except Miyagase have the western Tanzawa 丹沢山系 and Okutama 奥多摩山系 mountains as the catchment area where it rains a lot. Miyagase Dam 宮ケ瀬ダム asks the eastern Tanzawa only as its catchment area, but its capacity is the largest. The water offices connect Sagami 相模ダム and Shiroyama 城山ダム dams with Miyagase Dam by 2 large underground aqueducts to store water. In addition to this, the underground aqueducts also connect Iizumi 飯泉取水堰, Sagami 相模大堰 and Samukawa 寒川取水堰 waterintake facilities. Iizumi facility collects water from Sakawa River 酒匂川 stored at Miho Dam 三保ダム. Sagami and Samukawa facilities withdraw H2O from Sagami River 相模川 stored in Sagami, Tsukui, and Miyagase Dams. The connection among water facilities stabilizes water supply from these 2 rivers and distribute it to the population centers of the prefecture, including Yokohama. 

Lake Sagami created by Sagami Dam
Lake Tsukui created by Shiroyama Dam
Lake Tanzawa created by Miho Dam
Lake Miyagase, created by Miyagase Dam
Samukawa water intake facility on Sagami River

A prefecture where 1/3 of it is in the megalopolis Tokyo area, i.e. Yokohama, Kawasaki, Fujisawa, and Sagamihara, rarity of drought is an achievement. I understand the pride of officers for the prefectural government or the city halls in Kanagawa when they describe the arrangement from their wise water policy making and execution with a long-term view. Er, well, BUT, these days I felt the very beginning of the foresight would be thanks to the coincidence of the history. The lucky chance happened some 150 years ago from the now-largest “citizen” forest of Yokohama. And that was because Japan closed itself to the outer world between 1639 and 1854. In those days, I don’t think there was anybody who cleverly expected the 21st century waterworks system of Kanagawa. Taking a credit of drought-less Kanagawa should require some modesty. Now I explain you why I think so.

When Commodore Matthew Perry of the US prised open the Japanese door for westerners in 1854, Edo (Tokyo) government 徳川幕府 did not want to be physically near to the white-faced people at all. They first let the foreigners have their consulate in Shimoda of Izu Peninsula 伊豆下田, some 110K south from Tokyo, and Hakodate in Hokkaido 函館, about 800K north from Tokyo. Soon Imperialists’ gun diplomacy forced the Shogun to tolerate them nearer. In 1858, the Port of Yokohama, 20K south from the Edo Castle (now, the Imperial Palace), was opened. Even though, until 1899 Japan did not allow non-nationals to move around in the country. The concentration camp of foreigners in Yokohama was enforced for about 40 years. The port Europeans (; then, Americans became busy with their Civil War) had to stay that long was not so comfortable at the beginning. Before 1858, this part of the beach of Edo (Tokyo) Bay was salty swamps with occasional sandbanks for a small impoverished village of fishermen’s huts, called Yokohama Village. Inevitably for sandy places surrounded by salty swamps, the water quality was extremely poor. Before 1858, the area was frequently hit by the outbreaks of cholera. Do you remember in August 2015 we visited Yasaka Shrine 戸塚八坂神社 near Masakarigafuchi Citizen Forest まさかりが淵市民の森? The Shintoism Shrine is famous for the transgender festival every 14th of July. The carnival is said to be started in the 17th century to “pacify” demon of cholera. The shrine is about 8K inland from the newly established port.

Yasaka Shrine against cholera epidemic

In 1868, Edo Shogunate was replaced by Meiji Government 明治政府 who was eager to industrialize and imperialize Japan. Meanwhile, the new international port attracted lots of people from all over Japan who needed water too. The population of Yokohama exploded. In 1868, Yokohama already had 28589 residents including 1070 foreigners. By 1876, the population became 56048. For a while, the government let Yokohama to follow Tokyo about water. Some 300 years earlier, the place around Edo Castle 江戸城 was also a swamp. For centuries the Shogunate government reclaimed land, and built waterworks in ditch such as Tamagawa Josui Waterworks 玉川上水. In 1871, the mandarins for Yokohama made private entrepreneurs build ditches and carry water in wooden pipe from Tama River 多摩川, just like for Edo. According to Prof. Keiko Izumiof Iwate Prefectural University, the volume of H2O reaching to the new port in this way could not keep pace with the increasing number of residents. Worse, open-air ditches with hastily connected wooden pipes contaminated the contents at once. Outbreaks of cholera, again and again. In addition, rashly constructed new town was prone to large fire, and lack of water created the serious fire incidents. Water sellers with wooden buckets for exorbitant price did thriving business in Yokohama. On the other hand, luckily for westerners they had superior weaponry to Japan. They went like “OK, we stay at the place you designated for us. But, hey, you have to make our place nicer for our life in Japan. Otherwise, we’re gonna push you trade treaties that would extract silver, silk, and any Japanese goodies as much as possible while we are completely immune to Japanese law. By the way, our gun can kill Yokohama people easily whenever we want to.” The new government hated the international trade treaties concluded during the Shogunate. They had to provide good deals to invite westerners to the renegotiation table. i.e., Japan needed better infrastructure for Yokohama ghetto of foreigners. They realized private water business in old Edo style did not work.

A remnant of old wooden pipe
used for the private water business in Yokohama.
A water seller in early days of the port of Yokohama.
We can find these historical artifacts in
Yokohama Waterworks Commemoration Hall
It’s a fun museum with lots of exhibits
about mechanics of waterworks in Yokohama,
old and new.

So, in 1883, the Meiji government invited British Army Engineer Brigade Colonel H. S. Palmer to create project information documents to build a modern waterworks system for Yokohama. In his proposal, Palmer presented 2 water sources for Yokohama; Tama River and Sagami River. Kanagawa Prefectural government chose Sagami River since all the suggested water intake facilities from Sagami River was in Kanagawa Prefecture. (Ah-ha, so Kanagawa is historically stingy about water towards Tokyo!) The construction started in 1885 and the system for Yokohama became operational in 1887. It was the first modern waterworks in Japan, earlier than for Tokyo. For more than 150 years, the system continue withdrawing water from near Tsukui Lake, or, to be more exact, from a tributary of Sagami River called Doshi River 道志川. It sends water to Yokohama only by the gravitational pull created by the difference of elevation between the water source and Yokohama’s water purification plants some 53km apart; no pumping is used at all. From the beginning the network goes through the closed and sometimes underground pipes, which made it possible to convey the water to the destinations “as-is” at the intake facility. As Prof. Izumi pointed out, the design made the water quality at the source all the more important. All sound very difficult for a mega national project of the late 19th century. Why, then, could the endeavor be completed in only 4 years from the inception? Well, it’s because of the water source forest surrounding the water intake facility in Palmer’s design. It’s Doshi Village Water Source Forest 道志村水源林, owned by the city of Yokohama, but situated in Yamanashi Prefecture. That’s my topic next week. It’s a story possibly similar to the international relation along Mekong River, or for Rogun Dam of Tajikistan.

Doshi River along the Aoyama Settling Basin 青山沈でん池

Kanagawa Water Source Authority 神奈川県内広域水道企業団
1194 Yasashi-cho, Asahi-ku, Yokohama, 241-8525
Phone: 045-363-1111

Yokohama Waterworks Bureau 横浜市水道局
Phone: 045-847-6262
FAX: 045-848-4281

Friday, January 5, 2018

Treasure Tree: Lake Tanzawa and its surrounding forests 丹沢湖

Kanagawa Prefecture has 4 (main) water reservoirs: Lake Sagami 相模湖, Lake Tsukui 津久井湖, Lake Miyagase 宮ケ瀬湖, and Lake Tanzawa 丹沢湖. Created by Miho Dam 三保ダム in the mountains of West Tanzawa, Lake Tanzawa is the origin of Sakawa River 酒匂川. It is located near the border for Kanagawa 神奈川, Yamanashi 山梨 and Shizuoka 静岡 Prefectures, in Tanzawa-Oyama Quasi-national Park 丹沢大山国定公園. When you visit Lake Tanzawa by public transportation, please take commuter bus services from the bus terminal in front of Odakyu Shin-Matsuda Station 小田急新松田駅 by Fujikyu-Shonan Bus 富士急湘南バス. It’s the service to Nishi Tanzawa Visitor Center (西丹沢ビジターセンター West Tanzawa Visitor Center; time tables are here). There is only one route to reach to Lake Tanzawa. We have to take the same road anyway as the commuter service to go there by car. For automobiles, we get off Tomei Express Way 東名高速 at Ohi-Matsuda 大井松田IC to enter National Route 246. Please drive west along Tomei Express Way until observing Tsuburano Tunnel 都夫良野トンネル above, and turn right at Shimizubashi traffic light 清水橋交差点 after passing JR Yaga Station of Gotemba Line 御殿場線谷峨駅. That’s the way to enter prefectural route #76 heading north to Lake Tanzawa. About 10k drive from the traffic light and before entering Kaminawa Tunnel 神縄トンネル, we can glance at Miho Dam on the left. When we exit to the other side of the tunnel, Lake Tanzawa is spreading before us. There at a T-crossing, if we turn right, the route is now prefectural road #710 that ends at the entrance of West Tanzawa Citizen Forest of Kanagawa Prefecture 神奈川県西丹沢県民の森. If we turn left at the T-crossing, route #76 soon brings us to Kamioda community 神尾田 with the admin office of Miho Dam and tourism information center, named Lake Tanzawa Memorial Hall 丹沢湖記念館. We keep on going to cross Eisaibashi Bridge 永歳橋 and meet with another T-crossing. To the left, we enter prefectural route #729 via Ochiai Tunnel 落合トンネル. After driving for about 4K, #729 becomes for permit-holding construction cars only, which will end in the middle of forest. If you continue driving route #76, we go through Nakagawa Hot Spring Spa 中川温泉郷 and reach to the dead-end at Nishi Tanzawa Visitor Center. With all three driving roads, we run along the shore of Lake Tanzawa for a while, and will be terminated at the middle of mountain streams pouring to the lake. In short, Lake Tanzawa is in deep mountains almost at the end of place where automobiles can reach. And, that’s the reason why the place is so charming.

Sakawa River with Miho Dam over there
along prefectural road #76.
Lake Tanzawa seen from the mouth of Kaminawa Tunnel
Miho Dam.
It’s created by the same methodology
as Aswan High Dam of Nile River.
The other side of the dam is a calm mountain lake.

It seems to me, as always for a country side in the 21st century Japan, the community around Lake Tanzawa faces the problem of aging and shrinking population. At each bus stop for the services from Shin-Matsuda Station to Lake Tanzawa, especially after JR Yamakita Station 山北駅, we are greeted by a large notice board saying “This commuter service was reviewed jointly by the operator and the prefecture who concluded the continuation of the operation for citizens disadvantaged in transportation. The business is subsidized by the prefectural government and Fujikyu Shonan Bus Co. asks the customers to support our services to sustain the system.” Hmmmmm … Actually, Lake Tanzawa is popular among outdoor lovers in metropolitan Tokyo. Yamakita Town 山北町 which is the address for Lake Tanzawa has an agreement with Shinagawa Ward 品川区 of Tokyo by which the residents of Shinagawa can have preferential access to the fun facilities around Lake Tanzawa, such as tennis courts and allotments for Sunday farming. The lake community also hosts an annual half-marathon event every November, called Lake Tanzawa Half Marathon 丹沢湖ハーフマラソン. The area has a good infrastructure. Although the utility roads for automobiles do not go further from the Lake, there is a forestry road completely circling around the lake shore that is damned-well paved with good guardrails. For cars it is a forestry road accessible for permit-holders only; for walkers and bikers, it is a relaxing way around the lake. As Lake Tanzawa is a water-reservoir in deep mountains, the slope around the lake is inevitably covered by water source forests. So if you ramble in the circling road of Lake Tanzawa, you can experience water source forests of Kanagawa without venturing into the mountain itself. It is possible for wheelchairs to enjoy the water source forests. That’s really something.

“Thank you for your cooperation.
Fujikyu-Shonan Bus Co.”
One of the gates
entering into the forestry road surrounding the Lake

One fine winter day, I’ve been there and walked the forestry road around the lake. It was a very quiet strolling with a wide view of Lake Tanzawa. Around the lake is, I would say, 20% of afforested coniferous forests and 80% of natural trees. Steep slopes along the forestry road on the shore are treated with rockfall prevention works. Otherwise, natural soil goes up from the paved way. We can find footsteps of wild animals … deer, bear, boar, … just along the smooth car road. Well, even for wild animals, paved way could be easier to maneuver, couldn’t it? From the forestry road, I could spot pheasants having wormy lunch under trees over there. According to the exhibitions shown in the Tanzawa Memorial Hall 丹沢湖記念館, the area has more than two millennia history of human settlement. During Tokugawa Shogunate period 江戸時代, the forests in the west Tanzawa were owned by the lord of Odawara 小田原藩 who was a loyal follower of Shogun in Edo (Tokyo). The trees in entire Tanzawa were important resource for construction works and fuels in Edo. In the east Tanzawa which the Shogun directly owned, 6 kinds of trees 丹沢六木, Tsuga sieboldii, Torreya nucifera, Castanea crenata, Zelkova serrata, Abies firma, and Cryptomeria japonica, were closely protected as the property of Edo government. The lord of Odawara followed his master’s land management, and ordered the villagers in the west Tanzawa taking care of the trees as in the east Tanzawa. The present day beauty of natural forest around Lake Tanzawa is the product of this 400 years’ tradition. The construction of Miho Dam for 1969-1978 submerged several villages as a result, but the remoteness of the place spared it from the rampant development.

Lake Tanzawa Memorial Hall preserves a 200 years old house
that was once stood in the western part of Lake Tanzawa.
The place has lots of information about the history of the community.
It’s Seuret with infinite variation of pale green, grey, and brown
delicately dotted on a space canvas …
The circling “forestry road” for Lake Tanzawa
I think it’s Ursus thibetanus’.
The forestry road has lots of bridges
over the end of mountain stream pouring to the lake.
The forest surrounding the lake.
Hmmmm …
those grasses should have been “mowed” by deer.
Could you figure out
the remnants of the community road over there?
The below must have remains of the village.

For feeling what was like the area before Miho Dam, we can try walking prefectural road #76 north for a while. Lake Tanzawa eventually becomes Kouchigawa River 河内川. About 2K walk from the lake, we’ll be greeted by Nakagawa Hot Spring Spa 中川温泉郷 which has a legend of the 16th century warlord of Yamanashi Prefecture, Takeda Shingen 武田信玄, who used the place secretly as a sanatorium for wounded soldiers. Walking further to the West Tanzawa Visitor Center, we enter more and more into a deep mountain, with very few houses along the route #76. The very transparent Kouchigawa River flows rapidly, which is assuring as a water source for us in Yokohama. About an hour walk for 3K from the spa, we can find a small community with a gigantic Cryptomeria japonica on the left. It is Hohki Sugi (箒杉 Hohki cedar) in Hohki community . The cedar is estimated to be around 2000 years old, and in 1934 registered as one of the natural treasures of Japan. It is said that the villagers of Hohki has been taking care of the forest of the area for centuries, in accordance with the regulation set by the lord of Odawara. Their mountain was famous for its rich forest, and had the name Hohki 宝木 that is a homonym of Hohki  but whose Chinese character means “Treasure Trees.” During the period of the lord of Odawara, Hohki Sugi had its twin next to it. After Meiji Restoration 明治維新 of 1868, the lord of Odawara was replaced by rotating mandarins by the new government. Eventually the zeal of industrialization reached to this place and in 1908 Hohki sugi’s brother was cut down. The name of the community was changed to Hohki whose Chinese Character means “Broom.” Then in 1972, when a ferocious typhoon hit the area, Hohki Sugi and surrounding forests stopped the landslides along Kouchigawa River and protected the Hohki community. They did a perfect job as water source forests. Dependable 2000 years old …

Nakagawa Hot Spring Spa over there.
The entrance to spa.
We can stay there for days,
or just drop by to have an hour spa experience.
The Route #76 after spa.
During industrial revolution of Japan,
the road was upgraded for forestry use.
Now, it’s a very quiet commuter bus route
to West Tanzawa Visitor Center.
Kouchigawa River has really transparent flow.
Hohki Sugi over there

And I really have to tell you this: the area around Lake Tanzawa is the entrance to one of the main mountaineering routes to the peaks of Tanzawa Mountains. From Kurokura Bus Stop 玄倉バス停 to West Tanzawa Citizen Forest, we can start climbing to Mt. Nabewari (鍋割山 ASL 1272.4m) and Mt. Tonodake (塔ノ岳 ASL 1490.9m) via beautiful Yushin Valley ユーシン渓谷. From West Tanzawa Citizen Forest or West Tanzawa Visitor Center, we visit Mt. Azegamaru (畦ヶ丸 ASL1292.3m), Mt. Kanyudo (加入道山 ASL 1418.1m), Mt. Omuro (大室山 ASL1587.4m), Mt. Hinokiboramaru (檜洞丸 ASL 1601m), Mt. Hirugatake (蛭ヶ岳 ASL 1672.6m), and Mt. Tanzawasan (丹沢山 ASL 1567m). If you plan to climb these peaks, you should

(1) consider your mountaineering level first: the area is a daily training ground for Japanese mountaineers preparing for Mt. Everest;

(2) make an itinerary for at least 2 day hike from Tokyo with camping in refuge huts or staying mountain cottages near the peaks; and

(3) prepare yourself with enough water, food, and appropriate gears: during winter, equipment for snow could be MUST in Tanzawa’s main ridges.

Having said that, these are the peaks uber-popular in the metropolitan Tokyo area. It could be difficult to make a reservation at mountain cottages for weekends. It’s very interesting … such major destinations are important water source forests for us in Kanagawa. That would be why we have to play balancing act around Lake Tanzawa always. As in 400 years ago, these are the treasure trees near us.

I think the left one is Mt. Omuro.

If you find something unusual during your adventure around Lake Tanzawa, please make a contact with West Tanzawa Visitor Center. They also have a drop-box for your climbing registration that is very important especially here … in case you may need emergency-copter service from Yokohama. Their contact address is

Tanzawa-Oyama Quasi-national Park 丹沢大山国定公園・県立丹沢大山自然公園

West Tanzawa Visitor Center of Kanagawa Prefecture 神奈川県立 西丹沢ビジターセンター

867 Nakagawa, Yamakita-cho, Ashigarakami-gun, Kanagawa, 258-0201 神奈川県足柄上郡山北町中川867

Phone: 0465-78-3940

Friday, December 29, 2017

Mt. Fuji, falcon, aubergine

In Japan, there is a saying 一富士二鷹三茄子, meaning,

After going to bed on January 1st if you have a dream of Mt. Fuji, and/or falcon, and/or aubergine, you will have a lucky year.

(But, WHY!?)
I hope the above photo might be a help for all of you.

Season’s Greetings from Yokohama

Friday, December 22, 2017

On slicing a cake neatly: walking the “watershed” between Tokyo and Kanagawa 高尾山から小仏峠へ

I’m sure there are lots of travel guide in many languages for going to the peak of Mt. Takao 高尾山. So in my post this week, I just tell you a rough sketch in this part of my adventure in Mt. Takao. First, the nearest train station for the peak is Keio 京王線 Takao-san Guchi Station 高尾山口駅 whose name literally means “the entrance to Mt. Takao.” There are lots of route to visit the peak, and the standard ones go through the precinct of Yakuoh-in Temple 薬王院 where we can have Buddhism vegetarian dishes (RSVP). If you plan to go there in your business shoes or high-heels, you must use chair lift or cable car services by Takao Tozan Railway 高尾登山鉄道 that can bring us to the stations at ASL 460m (chair-lift) or 480m (cable car). From there to the peak, the main roads via Yakuoh-in are either paved, or decked so that approach is not so difficult. Otherwise, it is strongly recommended to wear your hiking shoes for Mt. Takao. As Mt. Takao sounds too familiar, people could go there without preparation and end up in hospital with a help of mountain rescue teams. Besides, if we want to immerse ourselves in the amazing biodiversity of Mt. Takao, we must divert from the paved roads as much as possible. Actually, the mountainous roads are more popular than cable cars, and could be congested in Mt. Takao. Trekking Road #6 becomes one-way up during every April 29 – May 5 and November, in order to ease “traffic jam” of hikers.

Takao-san Guchi Station
Kiyotaki 清滝 cable car station for Takao Tozan Railway
that is the beginning of the cable car service.
Just before the cable car station,
there is a junction between Omotesando
表参道 (meaning “the main approach”) to Yakuoh-in Temple,
 and two other hiking roads to the peak.
This is actually the beginning of Tokai Shizen Hodoh
(Tokai Nature Trail
More to this hiking road below.
When you get off the cable car from the foot of the mountain,
you’ll be welcomed by this small open space where
we begin to enjoy spectacular views.
This is to Sagami Bay
But if you don’t use public transportations from Takao-san Guchi Station,
the roads are standard trekking paths of Japanese mountain.
So, please be prepared.

Yakuoh-in, established in 744, is one of the training grounds for Yamabushi priests 山伏. The grand-masters of Yamabushi priests were often identified with tengu 天狗 with magical powers and the precinct in Mt. Takao has lots of tengu motifs. … After watching The Last Jedi, I felt the training of Yamabushi is like to be a Jedi … yeah, I’m serious. There are two water purification training 水行 spots for Yamabushi priests, or anybody who wants to do it (RSVP), in Mt. Takao … sounds more and more like the Jedi Temple for Rey … One in Mt. Takao is Hebitaki Fall 蛇滝, and another is Biwataki Fall 琵琶滝. Regrettably, just 20m underground of Biwataki Fall, there runs Takao-san Tunnel 高尾山トンネル of Kenoh-doh Express Way 圏央道 excavated by the technology for Eurotunnel. The route was opened in 2014. People said the road construction may have cut off the water vein of the area and could be a culprit for drying up of this sacred waterfall these days. Let us see what would happen in 10 years’ time … Oh, by the way, Biwataki Fall is along the most demanding trekking road of Mt. Takao. You have to wear your hiking shoes to visit there for sure. Training to be a Jedi is not at all easy, as all of us know.

All the roads coming from Takao Town meet
at the above open space in front of the cable car station.
From there, the boulevard to Yakuoh-in Temple runs to …
The main gate where
Mischievous sculptures of Tengu (goblin? fairy?) welcome us.
Yamabushi training spot at Biwataki Fall
From Oku-no-in of Yakuoh-in Temple,
a wooden-deck road leads us …
to the peak of Mt. Takao
where a visitor center
高尾山ビジターセンター is waiting for us.
The place is equipped with a small theatre and
many educational materials for science classes of grade schoolers.
The facility is always visited by kids.
Kstigarbha image at the peak,
calling for trash-free Mt. Takao.

Now, let me start telling you my adventure in honest from here. The view from the top of Mt. Takao, ASL 599.3m, is spectacular. To the east in a fine winter day, we can see Tokyo Skytree, Mt. Tsukuba 筑波山 and beyond. To the south are Bosoh Peninsula 房総半島, Tokyo Bay 東京湾, Miura Peninsula 三浦半島 and Sagami Bay where Enoshima Island 江の島 and Eboshi-iwa Rock 烏帽子岩 are floating. To the west is the entire Tanzawa Mountains 丹沢 where their highest, Mt. Hiruga-take 蛭ヶ岳 (ASL 1672.6m), is clearly commanding her pole position. And Mt. Fuji, of course. We also should observe the extremely rich vegetation around the peak of Mt. Takao. The mountain is located on the border between the warm temperate and the boreal, which made its forest consists of plants for both climates. In Tanzawa, we can meet beeches in the area higher than ASL 800m. Here in Mt. Takao, Fagus crenata is thriving already around the top. No wonder this is the most visited mountain in Japan every year. And that might become the reason of its misfortune ... Often people are amazed by the well-prepared walking path forever in Mt. Takao … but do you think rain can seep slowly in there? Is it really “nature friendly”? I just advice you to hold your lunch for 20-60 minutes more from the peak for a less-congested, but with equally spectacular views …

The view to Mt. Fuji from the top of Mt. Takao.
The highish mountain to the left of Mt. Fuji is
Mt. Omuroyama (ASL 1587.4m)
Further left is Tanzawa Mountains with the highest Mt. Hiruga-take.

2 trekking roads are departing from the top of Mt. Takao to the west, which join again within 5 minutes at a 5 roads junction. They are going into Oku-Takao, or deep Takao, although the roads are still fairly wide and well-constructed. The north-most road is going down a bit, where it is famous for its beauty in spring and autumn leaves. The middle one among the three to the west is running along the ridge, and in fine days, we can constantly observe Mt. Fuji from this road. The routes also have lots of benches. So, at whichever point you can enjoy your lunch. In addition, after the first junction, they will unite once more in about 600m so that you can choose any way to go to the west. Actually, this is the route designated as a part of Tokai Shizen Hodoh (Tokai Nature Trail 東海自然歩道), starting from the beginning of Omotesandoh of Yakuoh-in Temple. It’s a recreational walking trail created in 1973 with an initiation by the Ministry of Health and Welfare of Japan 厚生省. At that time, Japanese economy grew at a break-neck speed and environmental pollutions were damaging the health of the nation. In 1969 promoting healthy living in nature, an officer for the Ministry, Michio Ohi 大井道夫 who was in the office for National Parks, presented his idea of walking path to connect Tokyo’s Mt. Takao located in the middle of Meiji Forest Takao Quasi-national Park 明治の森高尾国定公園 with Osaka’s Mt. Mino’o 箕面山 (ASL 355m) in Meiji Forest Mino’o Quasi-national Park 明治の森箕面国定公園. Along the 1697km between the two mountains, Mr. Ohi deliberately chose biodiverse spots which were not-so-famous but relatively near to the population centers. The plan gathered enthusiastic supports from all over, and 11 prefectures along the way collaborated to provide safe walking roads for the project. It made many designated parts of the Trail Quasi-national Parks quickly. Unlike with Kanto Friendship Roads 関東ふれあいの道 (首都圏自然歩道), conquering all the way of Tokai Nature Trail does not give us honoring badges or the like. Even though, it is a very popular walking route and one of the reasons for Mt. Takao attracting such a lot of visitors. The itinerary goes not only nature sanctuaries, but also historical monuments dating back millenia. If you plan to live in Tokyo metropolitan area for a while, walking all the way from Mt. Takao to Mt. Mino’o could be a project of your life time. Actually, it’s in my bucket list. 😁 A journey of a thousand miles begins with a single step, or with Mt. Takao.

The junction with the 3 roads ahead from the top of Mt. Takao.
The middle road going up is the ridge way.
There are lots of signposts in the Mt. Takao Quasi-national Park.
Even western style toilets are provided.
The facilities in this Quasi-national Park is
so-called “eco-friendly toilets”
where flushing toilet papers are HUGE NO-NO.
After use, please throw them in a trash bin provided.
Thank you for your cooperation.
And the extremely well-constructed trekking road …

Tokai Nature Trail meets with the next junction for 6 roads. This time, let’s choose either of the 2 northern roads to the west. (The third path to the left descends to O’otarumi Pass 大垂水峠 on National Route 20 which was chosen in 2012 by Toyota Motor Co. as “one of the 86 most exciting Japanese passes for sports cars TOYOTA86峠セレクション.”) They will see each other in about 500m at Ichho-Daira 一丁平 with another toilets and a wide wooden deck for the view to Tanzawa-cum-Mt. Fuji. After Iccho-Daira, follow the signpost saying “To Shiroyama 城山.” In total of about 1 hour walk from the top of Mt. Takao, we reach to the peak of Mt. Shiroyama (aka Kobotoke Shiroyama 小仏城山), ASL 670.4m, where a café and a relay-tower for mobile phones are situated. For today’s itinerary, this is the last spot where we can observe Mt. Fuji and Tokyo Skytree simultaneously. When I’ve been there, watching Tokyo down below a group of hikers became very philosophical … “Hey, all of these are houses and buildings.” “Yeah, and people occupy almost all of them.” “Above all, we don’t know 99.99999% of the inhabitants who they are.” “… Yeah.” Also we won’t meet a toilet after this peak until we go down to Lake Sagami 相模湖. Please use the occasion wisely. The top of Mt. Shiroyama is the border and watershed between Tokyo and Kanagawa. Very roughly speaking, from now on the rain drops on the west slope of the ridge are supposed to end up at taps in Kanagawa via Sagami Lake. Those drops on the east slope should eventually join with Tama River 多摩川 in Fuchu City 府中市 so that they will never have a chance to be a part of waterworks of Tokyo … or will they? Tokai Nature Trail goes down from here, the peak of Mt. Shiroyama, to Lake Sagami. But in order to ponder more the water ways for Tokyo and Kanagawa, let’s continue for 30 more minutes along the ridge way to Kobotoke Pass 小仏峠.

At Iccho-daira just before Mt. Shiroyama,
Mt. Fuji is always there. Hello!
The top of Mt. Shiroyama.
In about 400 years ago, there was a mountain fortress,
hence its name Shiroyama = a mountain for a castle.
Seeing from Mt. Shiroyama, over there is the downtown Tokyo.
The Tokai Nature Trail goes down via the route starting next to the café.
Instead, we take this road next to the tower for continuing the ridge way.

Very interestingly, from Mt. Shiroyama to Kobotoke Pass the road becomes a familiar trekking road as we can find in Tanzawa. It’s indeed a border between Kanagawa and well-manicured Tokyo. After observing a bit Lake Sagami to the west, we arrive a viewing point with benches for Tanzawa / Mt. Fuji that is the last place for us today to admire the couple. About 100m from here, we reach to Kobotoke Pass 小仏峠, ASL 548m. The place now has a crumbling hut and a monument saying “Emperor Meiji visited here in 1880.” The reason why the place had a royal visit was, the road going through this pass from east to west was the original Koshu-kaido Road 旧甲州街道. Koshu-kaido Road was one of the 5 arterial roads 五街道 in Japan till Meiji Restoration 明治維新 of 1868, connecting Edo (Tokyo) and the middle of Honshu Island. For Tokugawa Shogunate Government 徳川幕府, Kobotoke Pass was an important checkpoint 小仏関所, just like Hakone Checkpoint 箱根関所, to defend Edo. Naturally, Kobotoke Pass is on the border between Edo (Tokyo) and Sagami (Kanagawa). Unfortunately, the way was too demanding for western style carriages, and later automobiles, so that in 1888 Meiji Government changed the route of Koshu-kaido Road to the current National Route 20. Inevitably, Kobotoke Pass was forgotten. Having said that, nowadays beneath the Pass, there run Kobotoke Tunnels 小仏トンネル for JR Chuoh Line 中央本線 and always congested Chuoh Expressway 中央自動車道 both of which trace almost the same route of the old Koshu-kaido Road. Hmmmmmm … at least in terms of a linear distance, ancient people really economized the way for connecting the Imperial Palace with the middle Japan.

A familiar mountain road in Kanagawa
Telling you the truth, the route to Kobotoke Pass is
a part of Kanto Friendship Road.
The photo point for badges is at the peak of
Mt. Kagenobu-yama
景信山 (ASL 727.3m)
about 40 minutes’ north from Kobotoke Pass.
Unfortunately, we don’t go there today.
The last encounter with Mt Fuji today.
Down there is Lake Sagami.
Rapidly going down to meet with the signpost
saying “Kobotoke Pass.”
The monument of royal visit, with an abandoned hut

So, today, we turn left here at Kobotoke Pass to take the old Koshu-kaido Road to Lake Sagami. i.e. We bid farewell to Tokyo, and enter the water source forest of Kanagawa. But, by reaching this far from Mt. Takao, honestly I felt a kind of human opportunism dissecting the mountain to argue “the rain drops on this slope is Tokyo, and on the other side is for Kanagawa.” Who knows when we slice the land the waterway would be neatly organized for Tokyo and for Kanagawa. Whatever, when we enter the forests in Kanagawa, we meet the familiar notices saying “This forest is water source forest of Kanagawa Prefecture.” OK, OK, OK. Eventually, we start to hear the exhaust of cars busily running in and out of Kobotoke Tunnel, and then encounter frequent services of JR Chuo Line below. Just before meeting with train tracks, there is a beautiful mountain stream coming down from the north going to Sagami River. It has an impressive name, Bijo-zawa Stream 美女沢, aka the “Valley of a Beautiful Lady.” The area has a folklore as a birthplace of Lady Terute 照手姫, a gorgeous and faithful lover who became a heroine in the Story of Oguri Hangan 小栗判官 for Kabuki 歌舞伎 and Joruri puppet shows 浄瑠璃. As a person who drinks tap water in Yokohama, I felt the name of the origin for my glasses is not bad. … And such an egoistic feeling to call “this water is mine” … The way from Kobotoke Pass to Sagami Lake is almost constant going-down, and finally we meet with National Route 20 at Sokosawa 底沢 Junction. You can either catch a Kanachu Bus Services from Sokosawa Stop 底沢停留所 to Sagamiko JR Station (timetable, here), or walk to Sagamiko Station 相模湖駅 for about half an hour via Route 20. If you choose to walk, about 500m from the bus stop, there is Oharajuku Honjin 小原宿本陣, a museum preserving a hotel for Samurai Lords centuries ago 本陣. It is the only remaining historical structure in Kanagawa Prefecture as one of the most prestigious hotels under Tokugawa Government. In the 21st century, the admission for the museum is free even for us commoners. Thank you. 😏

From Kobotoke Pass, we take this road to Lake Sagami.
Rain dropping over there is supposed to belong to Tokyo.
And this side is for Kanagawa.
We understand why people of the 19th century
decided to have a new route for Koshu-kaido Road
… But, beautiful, isn’t it?
Here it comes: “This forest is for Kanagawa’s water.”
Chuo Freeway is over there.
And JR Chuo Line.
The stream of beautiful lady
Sokosawa Bus Stop
Oharajuku Honjin

The contact address for the office in charge of Meiji Forest Takao Quasi-national Park 明治の森高尾国定公園 is

Bureau of Environment, Tokyo Metropolitan Government 東京都環境局
2-8-1 Nishi-Shinjuku, Shinjuku-ku, Tokyo, 163-8001
Phone:  03-5388-3539, FAX:  03-5388-1379

The contact address for the office in charge of Sagami Dam is

Enterprise Bureau, Kanagawa Prefectural Government 神奈川県企業局
1045 Nihon-Odori, Naka-ku, Yokohama 231-8588
Phone: 210-1111