Mitsui Family Residence Main House

An 1889 townhouse in the Higashi-koken quarter

The Mitsui Family Residence Main House (三井家住宅主屋, Mitsuike Jūtaku Shuoku) is a machiya townhouse built in 1889 at Higashi-koken in Inuyama City, Aichi Prefecture, and entered on the national register of tangible cultural properties in 2004 under the number 23-0144.

Inuyama grew below its castle as a merchant town, and the plot occupied by the Mitsui Family Residence Main House sits a short walk east of Honmachi-dori, the north-south spine of that town. The building faces north onto a lane. It is timber-framed, 2 storeys, and covers 129 square meters. Frontage runs just under 4.5 ken, roughly 8 meters, and the plan reaches back 7 ken, about 12.7 meters.

The roof is a plain gable, kirizuma-zukuri, laid with sangawara pantiles. Since the long eaves side rather than the gable end meets the street, the type is hirairi. Lean-to roofs, geya, run along the front and the back. At the west end the ridge steps down into a lower bay, an ochimune, which the household used as the kuramae, the working room set in front of the storehouse.

Why the Mitsui Family Residence Main House is on the register

The Agency for Cultural Affairs registered the building under the criterion for structures that contribute to the historic landscape of the country. Registration is a lighter instrument than designation: it obliges the owner to notify the state before altering the exterior, and it leaves the house in daily use. Inuyama has taken up that instrument on a scale unusual for a city of its size. Counting the buildings put forward in 2025, the city holds 158 registered structures, close to 27 percent of the 580 registered in Aichi Prefecture.

The Mitsui Family Residence Main House is filed under tertiary industry rather than housing, which is the register's way of recording that the ground floor was a shop before it was a parlour. A room of 15 tatami mats, the mise-no-ma, occupies the street side of the plan.

Its date carries weight as well. Inuyama City's own survey of the castle town notes that most of the surviving townhouses were raised in the Edo period and then repaired after the Nōbi earthquake of 1891. The Mitsui Family Residence Main House had been standing for 2 years when that earthquake struck, which places it among the small number of houses on this street whose construction can be fixed to a year before the disaster rather than to the rebuilding that followed.

Reading the front from the lane

Stand back far enough to see the eaves. They project on beams cantilevered out from the wall plane, a technique called dashigeta-zukuri that lets the roof throw its shadow well clear of the shopfront. On a narrow lane the effect is easy to miss until you notice that the upper storey seems to hang over you.

The two floors are screened differently. Wooden lattice closes the ground floor. Iron lattice closes the upper floor. Inuyama's conservation plan describes mushiko-mado plaster grilles and renji-goshi wooden bars as the ordinary vocabulary of this townscape, so the ironwork on the Mitsui Family Residence Main House is worth a second look. It reads as a security measure on a merchant's upper storey, and it gives the facade a harder line than its neighbours.

Follow the wall west and the roof drops. That step is the ochimune, and beyond it the storehouse of 1918 begins, its gable turned to face the lane. Walk the other way, to the east end, and roughly 1.5 ken of the frontage is given over to the toriniwa, the earth-floored passage that runs the depth of the house. From that passage a single-storey wing, the connecting corridor, extends south into the back garden. Three separate registrations, one household, one continuous roofline.

Visiting the Mitsui Family Residence Main House

The house remains in private ownership, and Inuyama City's list of registered properties records the owner simply as a private individual. There is no interior access, no admission desk and no opening hours. What you can do is look at it from the public lane, which is where the registered value of the building lies in any case.

Photographing the exterior from the street is unproblematic. Do not step onto the plot, do not photograph through the lattice, and keep in mind that people live here.

From Meitetsu Inuyama Station, take the west exit and walk about 13 minutes north through the castle town. Inuyama Castle stands roughly 600 meters further north. Anyone who wants to see the inside of a townhouse of this kind can walk about 200 meters south to the former Isobe Family Residence on Honmachi-dori, a city-run building whose interior is open without charge from 9:00 a.m. to 5:00 p.m.

Early morning suits the Mitsui Family Residence Main House best. The lane is quiet, and low light rakes across the lattice and the projecting eaves in a way that the flat overhead light of midday flattens out.