Oka Naosaburo Shoten Omama Factory Library

The Storehouse Built for Paper

The Oka Naosaburo Shoten Omama Factory Bunkogura (岡直三郎商店大間々工場文庫蔵, also written Oka Naosaburō Shōten, Bunko-gura) is a two-storey dozo-style earthen storehouse at 1013 Omama, Omama-cho, Midori City, Gunma Prefecture, raised in 1913 and entered on the national register of Tangible Cultural Properties on 24 December 2013 under registration number 10-0307.

Most storehouses in a brewing compound hold something you can taste. This one did not. A bunkogura is a document store, and the Oka family built theirs to keep the account books of the soy sauce business out of reach of fire. Midori City's description of the property is specific on the point: the ledgers went in here.

That makes it a small building with a disproportionate job. Measured across the ridge it runs 9.4 metres by 4.6 metres, giving a registered building area of just 44 square metres, roughly five ken by two and a half. The firm's paper record of two centuries of trade fitted inside that footprint.

How It Is Built

The Bunkogura stands north of the store and main house, its ridge running east to west while the older building faces the street to the east. The two together are what the registration singles out, since the criterion applied is contribution to the historic character of the national landscape, and neither structure makes the streetscape on its own.

Construction is dozo-zukuri, the thick mud-wall technique that Japanese merchants relied on before insurance existed. Timber posts are packed with layered earth and finished outside in white lime plaster. The roof is gabled and laid with sangawara pantiles. The base is cut andesite, a hard volcanic stone that resists rising damp and shifts less than rubble footing, and a mizukiri drip course runs around the wall to throw rainwater clear of the plaster below.

The entrance is on the south face, turned toward the main house rather than the street. Windows are set on the south and east faces of the upper floor only. Both the doorway and the openings are hung with kakego-nuri doors, in which the leaf and the jamb are plastered in matching stepped rebates so that when the door swings shut the joint closes on itself. That detail is the whole argument of the building. Smoke and embers travel through gaps, and a storehouse full of paper cannot afford gaps.

The year of construction matters too. The frame was raised in 1913, the second year of Taisho, eighteen years after the Omama fire of 1895 had burned through much of the town. A merchant house that had watched its neighbourhood burn once was not going to keep its ledgers in a wooden room.

Seeing It, and What Is Around It

The Bunkogura is not open as an exhibition space and there is no interior tour of it. What you can do is look, and it repays looking from the right angle. Coming along the street from the north you catch the plastered gable end and the crisp line of the drip course before the shop front comes into view. The plain white mass reads very differently from the lattice-windowed frontage of the main house beside it, which is precisely the contrast the compound was designed around: display at the front, security behind.

Access to the site is free and the shop in the main house opens without an admission charge. The company also runs a free guided tour of the working fermentation storehouse, separate from the Bunkogura, lasting about fifteen to twenty minutes, with sessions announced for 10:00, 11:00, 13:00, 14:00, 15:00 and 16:00. Parties of ten or more need to telephone ahead, and busy brewing periods can close the tour, so it is worth calling whatever the size of your group. Inside it are wooden vats over a century old, still in use.

Omama Station on the Watarase Keikoku Railway is about five minutes away on foot, Akagi Station about thirteen. Parking is free. The compound has steps and uneven ground and is not wheelchair accessible. Photography is not covered by any published rule and the site is a working food factory, so check at the shop counter first.

If you are making a day of it, the surrounding blocks of Omama hold more of the same period. The Midori City Omama Museum occupies the former Omama Bank building of 1921, and the Nagame Yokyojo of 1937 is a rare surviving wooden playhouse. Both are within walking distance, as is the Takatsudo Gorge on the Watarase River.