Oka Naosaburo Shoten Omama Factory Store and Main Building

A Meiji Shop-House That Never Stopped Trading

The Oka Naosaburo Shoten Omama Factory Store and Main House (岡直三郎商店大間々工場店舗兼主屋, also written Oka Naosaburō Shōten) is a two-storey timber merchant building at 1013 Omama, Omama-cho, Midori City, Gunma Prefecture, put up in the middle Meiji period between 1883 and 1897 and added to the national register of Tangible Cultural Properties on 24 December 2013 under registration number 10-0306.

It faces east onto the old road through Omama, which is the same road it has faced since it was built. The building is not a preserved shell. Walk in through the front and you are standing in a soy sauce shop that opens for business, run by the company that has been brewing here since 1787.

Oka Naosaburo Shoten was founded in the seventh year of Tenmei, 1787, by Oka Chubei, a merchant from Omi Province (present-day Shiga Prefecture). Omama was then a post town on the Akagane Kaido, the "copper road" that carried ore down from the Ashio mine toward Edo. A trading family that set up along that route had customers, carters and cash passing the door every day. The company still brews under the trademark Nihonichi Shoyu, and its head office is now in Machida, Tokyo, with production concentrated at this Omama site.

Why the Building Was Registered

The registration criterion applied here is the one covering buildings that contribute to the historic character of the national landscape. In plain terms: this structure gives the street its face.

A fire tore through Omama in 1895, the twenty-eighth year of Meiji, and destroyed a great deal of the town. This building escaped. That single fact is why the exterior still reads as a Meiji commercial frontage rather than a post-fire rebuild, and it explains why the Oka compound, with its row of large earthen storehouses from the Meiji and Taisho years, now stands out so sharply along the street.

The structure is timber-framed, two storeys, with a gabled roof of sangawara pantiles and plastered white walls. Look up at the second floor and you will see two horizontal lattice windows set to the left and right of the frontage, with sode-udatsu at either end: short projecting fire walls, finished here with moulded cornices, that a merchant raised partly against fire and partly to advertise that he could afford them.

The plan is divided front to back. The southern half of the interior is the shop; the northern half held the office, the tatami reception rooms and the household space. Behind the shop portion a brick chimney still stands, a survivor of the days when the fire for the household and the business was in the same building. Midori City's own account of the property gives the shop block as roughly eight ken by five and a half ken, with the residential wing added on in an L-shaped, magariya-style extension by about 1900 to house the manager sent up from Omi. Total registered building area is 216 square metres, and the registration takes in the gate and the chimney as well.

What to Look For, and How to Visit

Start outside. The two udatsu at the roof ends are the quickest read on the building's status, and the lattice windows above the entrance are worth a minute of attention because their proportion is unusually wide and low. Step back across the road if you can. The chimney rises behind the roofline and gives away what the front elevation politely does not: that this is a factory as much as a house.

Inside, the shop was refurbished in 2012 using traditional restoration methods rather than being gutted, and a good deal of the original fit-out survives in plain sight. The company points visitors to the old kamado cooking hearth, the tatami room, the safe and the telephone booth, all still in place among the shelves of bottles. There is no admission charge to enter the shop.

The brewery tour is the other half of a visit. Guided tours of the fermentation storehouse are free and take about fifteen to twenty minutes, with departures announced for 10:00, 11:00, 13:00, 14:00, 15:00 and 16:00. Groups of ten or more should book in advance by telephone, and tours can be suspended during busy brewing periods, so a call ahead is sensible even for two people. Inside the storehouse are wooden vats that have been in continuous use for more than a century.

Getting there is easy. Omama Station on the Watarase Keikoku Railway is about a five-minute walk; Akagi Station, served by Tobu and Jomo lines, is roughly thirteen minutes on foot. There is free parking on site. One practical warning: this is a Meiji building with steps and level changes, and it is not wheelchair accessible.

Photography rules are not published, and the site is a working food factory, so ask at the counter before taking pictures inside the shop or the brewing storehouse. Within a few minutes' walk you will also find the Midori City Omama Museum, housed in the former Omama Bank building of 1921, and the Nagame Yokyojo, a wooden theatre of 1937. The Takatsudo Gorge, cut by the Watarase River, is a short walk south.