A banker's villa carried to the mountains
The main house of Seiho Sanso began life far from the mountain that now surrounds it. Built in 1913 as the villa of Kimura Seishiro, the tenth deputy governor of the Bank of Japan, it first stood in Tokyo. The Ehara family took it in and moved it to Suginami in 1936, then relocated it once more, in 1985, to the southern foot of Mt. Akagi where it stands today.
It is a single-storey wooden residence of 188 square metres. A visitor enters from the west and passes through a run of connected zashiki rooms toward the east, with a Western-style room set at the south-west corner. The name Seiho Sanso joins one character from Kimura Sei-shiro with one from Ehara Yoshihei, the family head who received the house, a small record of a friendship kept in the name.
A refined modern Japanese house
Registered as a Tangible Cultural Property in March 2025, the house is valued as a fine example of modern Japanese domestic architecture, the kind that sets native rooms beside Western comfort. The formal zashiki keeps the full set of a traditional reception room: a tokonoma alcove, staggered shelves, and a built-in study window (tsuke-shoin), all in good timber.
The Western room answers with a wooden mantelpiece. Look up and the ceilings and window fittings carry a worked pattern of interlocking well-crib squares (igeta) and diamonds (hishi), decoration that rewards a slow second glance.
Visiting
The estate is entered through a long nagaya-mon gate whose wooden signboard was brushed by Nakasone Yasuhiro, the former prime minister and a son of Gunma. From the gate it is a two-minute walk, or a short drive, to the house, a measure of how wide the grounds are.
Today the building is the centrepiece of Seiho Sanso, a cultural hotel run on the Ehara estate that takes only a few groups a day. Its main room runs to some 40 tatami, and the garden shifts with the seasons around it. Guests, rather than day callers, are the ones who sit inside.
- 📍 Plan Your Visit to Gunma
- Find tours, activities & transport passes near Ebara Honke Seiho Sanso (former Kimura Seishiro Residence)
- [ Kusatsu Onsen & Tomioka Silk Mill Heritage Tours ]
Q&A
- Who was Kimura Seishiro?
- He served as the tenth deputy governor of the Bank of Japan. This house was built in 1913 as his private villa before it passed to the Ehara family.
- Why is it called Seiho Sanso?
- The name combines the 'Sei' of Kimura Seishiro with the 'Ho', read yoshi, of Ehara Yoshihei, the family head who received the house, marking the tie between the two men.
- Can the public visit?
- The house is the main building of the Seiho Sanso hotel and is open to overnight guests by reservation. Day-visit access is not offered, and guest numbers are limited.
- How many times was the house moved?
- Twice. It went from Tokyo to Suginami in 1936, then again to Mt. Akagi in 1985, which is why its 1913 fabric now sits in a mountain garden.
Basic Information
| Name | Ehara Honke Seiho Sanso (Former Kimura Seishiro Residence) |
|---|---|
| Location | Ryu-no-kuchi, Akagisan, Fujimi-machi, Maebashi, Gunma |
| Designation | Registered Tangible Cultural Property (Building), reg. no. 10-0353 |
| Registered | 13 March 2025 |
| Structure | Single-storey wooden residence, pantiled roof, 188 m² footprint |
| Period | Taisho 2 (1913); relocated 1936 and 1985 |
| Owner | Gunma Building Co., Ltd. (private) |
| Access | Main building of Seiho Sanso hotel; open to guests by reservation |
References
- 国指定文化財等データベース — 江原本家清芳山荘（旧木村清四郎邸）
- https://kunishitei.bunka.go.jp/bsys/maindetails/101/00015279
- 群馬県 文化遺産課 — 群馬の文化財
- https://www.pref.gunma.jp/page/5190.html
- 赤城宿 清芳山荘 — 施設案内
- https://akagi-shuku.com/hotels/seiho-sanso/
Last verified: 2026.07.03