From Ohara Tunnel to Katabira-cho Sugiyama Shrine: Ooka River Travelogue (3)
Continuing from last time
In heading to the next destination, I decided to dare to climb the hill behind Ota Sugiyama Shrine.
Minami-Ota 2-chome Friend Park
This is a park that makes use of the space under the elevated Metropolitan Expressway Kariba Line. Come to think of it, there was also a lovely park under the elevated road in Kawashima-cho along the Katabira River.
Lion-head public water tap
Under the arch on the opposite side of the park, there is a classic structure...
This appears to be a water facility called a lion-head public water tap.
Ohara Tunnel
As I climbed further up the slope, a tunnel that seemed to invite me into another world suddenly appeared in front of me!
Oh, it's a civil engineering heritage site! But what does 'related to the Yokohama waterworks' mean?
And it's quite long, too!
This Ohara Tunnel was completed in 1928 (Showa 3) as a tunnel for laying water mains as part of the reconstruction project following the Great Kanto Earthquake.
It is a horseshoe-shaped tunnel with a length of 254 meters, a height of 3.62 meters, and a width of 2.44 meters, with a gradient of 1 in 200, and although there have been slight changes to the height and width due to renovation work, a water main (610mm diameter) to the Makita/Isogo area is still buried inside the tunnel today.
A major feature of this tunnel is that the portal is designed with a unique sense of style, using purple-brown over-fired bricks in a French bond pattern, where the long and short sides of the bricks are alternated, and contrasting this with granite arranged like gate pillars to provide a powerful accent.
Like the Ohara Tunnel, the Higashi Tunnel in Iwai-cho, Hodogaya-ku, which is also decorated with French-bonded over-fired bricks and granite, is a sibling tunnel built for the same purpose around the same time. Both are tunnel structures recognized as representative civil engineering heritage sites in Yokohama.
I see, the lion-head public water tap I saw earlier was also related to the water supply.
According to Wikipedia, construction began in June 1927 and was completed in July of the following year. The total construction cost was 72,564 yen and 40 sen at the time. I wonder how much that would be today?
Converting it using the Corporate Goods Price Index (2024 is about 820 times that of 1927) comes to just under 60 million yen, but that seems too cheap. So, converting it based on the theory that "1 yen in the first year of Showa is 4,000 yen today", it comes to about 290 million yen (though this might still be cheap).
French bond is a masonry style where the short and long sides of the bricks are arranged alternately, creating a beautiful appearance. The purple-brown over-fired bricks create a sense of gravitas. Old over-fired bricks were fired in places near the heat source inside the kiln, making them harder and more densely fired than red bricks, and because they have low water absorption, they are also highly durable.
[Reference]
Chapter 40: Ordinary Bricks, Japan Society of Civil Engineers
http://library.jsce.or.jp/Image_DB/s_book/jsce100/pdf/03260/03260_06.pdf
Shimizugaoka Park seems to be a sacred place for Yuzu fans, and apparently there was also an observation deck with a good view.
Higashi Tunnel
If you leave the park and walk straight ahead, there is another tunnel!
Higashi Tunnel is a tunnel located in Iwai-cho, Hodogaya Ward, about 600m north of Ohara Tunnel. Like Ohara Tunnel, it was built for laying water pipes and features a similar design. Completed in 1930, it now serves as a local road connecting Hodogaya Station with the residential areas of southern Iwai-cho and Shimizugaoka, as well as Seirei Yokohama Hospital.It is 168.7m long, 6.3m high, and 5.7m wide, and while it is accessible to cars, it is narrow and lacks sidewalks, requiring caution for both drivers and pedestrians. Like railway tunnels, it has refuge bays at various points. In particular, although the frequency is low, it is also a route for local buses, so large route buses travel through this tunnel. It was designated as a Yokohama City Certified Historical Building and a Japan Society of Civil Engineers Selected Civil Engineering Heritage site at the same time as Ohara Tunnel.
Modern Waterworks of Yokohama
From the perspective of cholera prevention in the foreign settlement, the British Minister to Japan and others requested the Kanagawa Prefectural Governor to develop a water supply system, leading to the construction of Japan's first modern waterworks in Yokohama. Water taken from Mitsui Village, Tsukui District, Kanagawa Prefecture (present-day Lake Tsukui) was sent 48km to the Nogeyama Water Treatment Plant (elevation 50.6m) to supply water to the settlement. The Nogeyama Water Treatment Plant was damaged in the Great Kanto Earthquake, and the former Nogeyama Distribution Reservoir (still in existence) was completed in its place (1930).
Ohara Tunnel was built as part of the earthquake reconstruction project for water facilities to supply water to the southern part of Yokohama, where the urban area had expanded. It was designed to allow people to pass through as a maintenance passage and was later converted into a local road. To its north is the Higashi Tunnel (completed in 1930), which was also built for water pipes; because their designs are similar, they are called the sibling tunnels.
The Threatening Cliff
After passing through Higashi Tunnel and going straight down the slope, I arrived at Hodogaya Station.
I proceeded toward Yokohama along National Route 1, which runs parallel to the Tokaido Line. (Perhaps I should call this the Imai River travelogue, a tributary of the Katabira River, from here on...)
On the way, the view from Anraku-ji Temple was threatening!
In times like this, I use the cross-section function of the Geospatial Information Authority of Japan map to check.
A 40m-high sea cliff of the Shimosueyoshi Terrace. They built a railway under a cliff like this...
(It is said that slope collapse debris reaches a distance twice the height of the slope.)
Whether riding the Tokaido Line or driving on National Route 1, I never noticed it at all. It is covered with retaining walls, but it is amazing that it hasn't collapsed until now.
Katabira-cho Sugiyama Shrine
Just ahead, a pure white torii gate caught my eye.
It is no exaggeration to say that this place is dedicated to the cliff (just like the Ota Sugiyama Shrine).
History and origins, etc.
Sugiyama Shrine: Located in Shimo-Iwama-cho, in the eastern part of the post town. It is situated about two cho southeast of the Tokaido road. As it is an ancient shrine, this shrine must have been a branch of that shrine*. The local deity is a seated statue of Fudo, about one shaku in length. The main shrine is eight shaku square, with an outer building measuring one and a half ken by three ken. A torii gate stands in front, and there are stone steps before it. The annual festival is held on September 28th every year, and it is maintained by Enpuku-ji Temple in this location.
Sub-shrine: Kojukue Inari Shrine, located to the left of the main shrine.
* Refers to the Sugiyama Shrine, which is listed in the Engishiki.
During the Edo period, it was part of Katabira-cho (which had a wide area), so it is called Katabira-cho Sugiyama Shrine, but since it is now in Nishikubo-cho, it is also called Nishikubo Sugiyama Shrine.
According to the Fudoki Ko, the Odawara-shu Toryo Yakucho (Record of Odawara Domain Feudal Duties) mentions a place called 'Ko-katabira' (pronunciation unknown) in the Kojukue territory, which was held as a fief by Ota Shin-kuro (Yasusuke), a descendant of Ota Dokan. This area also seems to have deep ties to Kojukue.
Also, the Kanagawa Prefecture Shrine Records state that 'it is said that in ancient times it was called Misu Shrine and later, the shrine name was changed by adding the name of the local land steward, Sugiyama.'
I looked up Misu Shrine, but there is no information. Could it be pronounced 'bishu,' meaning beautiful beard? 'Bishu Gobi' is a term describing a sturdy man with a beautiful beard and thick eyebrows. Did it lead to 'Sugiyama' from 'Susanoo's beard = Sugi (cedar/cryptomeria)'?
Furthermore, what era's land steward would use their own name for a shrine? (I don't think a land steward, or hatamoto, would have such power during the Edo period, as the areas along the highway were under direct shogunate control.)
The enshrined deity is Isotakeru-no-Mikoto so I assume they invited a branch of the Sugiyama Shrine from the same lineage in the Tsurumi River water system, but...
Shrine location
Looking at a map from the Meiji era, the oldTokaido was on theopposite side of the Imai River, a tributary of the Katabira River. This means they built the railway on the right bank where there were no houses. But perhaps they had no choice but to build it along the mountain route because the ground along the river was soft.
Sugiyama Shrine stood with a cliff at its back, in the middle of rice fields on the outskirts of the post town. However, since the Hodogaya Road leading to Hodogaya-juku passed in front of it, it may have been an important point for transportation.
The Ota Sugiyama Shrine from last time was also located at the foot of a cliff near the river. Since there are several examples of Sugiyama Shrines located at the foot of cliffs, I am indulging in the fantasy that they might have been enshrined there in the hope of preventing landslides.
This time, I enjoyed unique terrain and historical sites, including mountains, tunnels, and cliffs. I would like to summarize the mystery of the development of Sugiyama Shrines in the Ooka River and Imai River basins at a later date.