Otani Family Residence Middle Storehouse

The Otani Family Residence Middle Warehouse: A Black-Clad Storehouse on Fukushima's Old Salt Road

Standing quietly along a historic trade route in the coastal plains of northern Fukushima, the Otani Family Residence Middle Warehouse (Ogai-ke Jutaku Naka-gura) is a striking black-walled storehouse that once held casks of sake and soy sauce for one of the region's most important merchant families. Built during the early Showa period, this two-story earthen warehouse is one of three structures — together with the East Warehouse and the Korai-mon gateway — that were registered as National Tangible Cultural Properties in 2016. Today, the Middle Warehouse has taken on an unusual second life: it houses the Tochikubo Postal Agency, making it one of the very few post offices in Japan to operate inside a designated cultural property.

Historical Background

The village of Tochikubo, in what is now the Kashima ward of Minamisoma City, grew up along the so-called "Salt Road" (Shio-no-michi) that linked the coastal Hama-kaido with the inland Oshu-kaido. This was a lifeline route along which salt, dried fish, rice, sake and other essential goods were transported between the Pacific coast and the mountain provinces.

The Otani family was one of the key merchant houses sustaining this inland-coastal trade. Their residence occupied a strategic position facing directly onto the road, a placement that clearly signaled their role as a commercial and logistics hub. Over generations the family accumulated a compound of practical buildings arranged to handle the storage and transfer of valuable commodities, with each warehouse dedicated to a specific class of goods.

The East Warehouse, the elder of the two storehouses, was built in the late Meiji period and served as the rice storehouse. The Middle Warehouse and the gateway that stands between them were added in the early Showa period, with the Middle Warehouse specifically designed for the storage of sake and soy sauce. The buildings' deep black exterior is not merely a stylistic choice: the walls were coated in black paint during the Second World War as a camouflage measure against air raids, and that wartime appearance has been preserved to this day.

Why It Was Registered as a Cultural Property

On August 1, 2016, the Otani Family Residence Middle Warehouse was registered as a National Tangible Cultural Property together with the East Warehouse and the gate. The registration recognizes not only the architectural quality of the individual storehouses but also the townscape value of the ensemble as a whole.

The significance of the property can be summarized in several points. First, the two earthen warehouses flanking a formal Korai-mon gate and facing directly onto the old highway form a symbolic landscape of the Tochikubo district, preserving the visual memory of a merchant family's logistics compound in a way that has become increasingly rare across rural Japan. Second, the warehouses display a high level of craftsmanship in their decorative elements, including elegantly laid "sea cucumber walls" (namako-kabe) around the lower courses and ornamental swirl-pattern bands (uzumon-iri hachimaki) wrapping the upper walls — features that were typically reserved for the storehouses of wealthy and well-established merchant households. Third, the buildings retain an extraordinary amount of wartime and postwar context, from the blackened exterior paint to the continuous community use that has allowed the structures to remain in good condition.

Architectural Highlights

The Middle Warehouse is built in the traditional dozo-zukuri earthen storehouse style, with thick fireproof walls made of layered clay and plaster over a wooden frame. It is a two-story building of roughly fifty-four square meters, capped with a sheet-metal roof that replaced older tile or shingle roofing to improve durability.

Several features deserve close attention when visiting:

• Namako-kabe (sea cucumber walls): The lower portion of the exterior is finished in a distinctive diamond pattern of square tiles joined by raised white plaster ridges. The name comes from the way the rounded plaster lines resemble sea cucumbers. This treatment was both decorative and protective against rain and splashing mud.
• Uzumon-iri hachimaki: The upper walls are wrapped in a decorative band featuring swirl motifs, a flourish that gives the otherwise utilitarian storehouse an air of celebration and prestige.
• Black-painted exterior: The deep, uniform black finish that covers the storehouse is the result of wartime air-raid camouflage. Where other historic storehouses have since been repainted white, this property preserves its wartime skin intact — a rare physical record of civilian life on the home front.
• Gateway ensemble: The East Warehouse, the Middle Warehouse and the Korai-mon gate between them form a deliberately composed street-facing group. Viewing the three together from across the road gives the best sense of what the approach to a prosperous Meiji-Showa merchant house actually looked like.

Visitor Information

The Otani Family Residence is still a private home, so the interior of the main house is not open to the public. However, because the Middle Warehouse now functions as the Tochikubo Postal Agency, visitors can step inside during business hours to experience the unusual atmosphere of a working post office set inside a century-old earthen storehouse. Seasonal flowers are sometimes arranged in the entrance, reflecting the thoughtful care of the resident family who operates the branch.

The exterior of the ensemble — the two storehouses and the gate facing the old road — can be appreciated from the public street at any time. Visitors are asked to be mindful that this is an active residence and a working post office, and to refrain from entering beyond the gate without permission.

Access

The property is located in the quiet rural hamlet of Tochikubo-Kozuka in the Kashima ward of Minamisoma City. From JR Joban Line Hitachiki Station, the site is about 4.4 kilometers away, best reached by taxi or rental bicycle. By local bus, travelers can board the Fukushima Kotsu bus from "Kashima Ekimae" and alight at "Kan'i Kyoku Mae" (literally "In Front of the Simple Postal Office"), from which the property is roughly a one-minute walk.

Surrounding Attractions

Tochikubo and the wider Kashima ward of Minamisoma offer a surprisingly rich cluster of heritage sites within a short drive.

• Sakamine Shrine Sacred Forest: Also located in Tochikubo, this shrine is surrounded by a city-designated natural monument — a mixed grove of Japanese nutmeg, zelkova, konara oak and red oak that hints at the original warm-temperate forest of the region.
• Mano Kofun Group: A nationally designated historic site in Kashima ward, this late Kofun-period burial cluster has produced extraordinary finds, including rare gilt-bronze fish-shaped pouch fittings.
• Kashima Mikoshrine: Home to a massive zelkova tree designated as a prefectural natural monument, estimated at between 900 and 1,200 years old.
• Amidaji Temple: In the nearby Minamiyakata district, this temple preserves several important Kamakura-period embroidered hanging scrolls and a great ginkgo tree.
• Minamisoma Museum: A good general introduction to the archaeology, folk culture and Soma horse-riding traditions of the region.