What Sapporo nanseki is
Sapporo nanseki, literally Sapporo soft stone, is a building stone quarried chiefly in the Ishiyama district of southern Sapporo. Geologists call it Shikotsu welded tuff. According to the Sapporo Central Library, it formed about 40,000 years ago when pyroclastic flows from the eruptions that created Lake Shikotsu poured across the Sapporo area and cooled.
The stone is soft enough to cut easily and resists fire and heat loss well, so it became a standard building material in Sapporo from the Meiji era onward. Quarrying at Ishiyama ended in 1978, though the city notes that production continues upstream in the Tokiwa area of the same ward.
Its use went well beyond the city that gives it its name, and covered government offices, churches, merchants' storehouses and farm warehouses alike. A citizens' survey has counted some 400 nanseki buildings in Sapporo alone.
In the records, and what to look for
National records treat the stone as emblematic of modern Sapporo. Of the former Sapporo Court of Appeals, built in 1926 and designated an Important Cultural Property, the Agency for Cultural Affairs writes that it is among the largest surviving buildings in Sapporo nanseki and displays a wide range of stone-working techniques. Its walls are load-bearing stone and brick.
Domestic outbuildings use it too. At the Endo residence in central Sapporo, from around 1919, three sides of the 161 m perimeter wall are nanseki, finished with a rough rock face and laid in alternating courses of different heights, and the storehouses on the plot are built of the same stone in level courses.
On site, look at colour and texture: a pale stone, often showing fine grains and small voids. Records sometimes specify the finish, rough rock-faced or dressed smooth. Oya stone from Tochigi is also a tuff but a different stone, from a different source.
References
- Sapporo City Library: Exhibition on Sapporo nanseki (Japanese)
- https://www.city.sapporo.jp/toshokan/sapporosiryo/201606nansekitenji.html
- Sapporo Central Library: Sapporo nanseki exhibition leaflet (Japanese)
- https://www.city.sapporo.jp/toshokan/sapporosiryo/documents/sapporonanseki2.pdf
- Agency for Cultural Affairs, Database of National Cultural Properties: Former Sapporo Court of Appeals
- https://kunishitei.bunka.go.jp/bsys/maindetails/102/00005321
- Agency for Cultural Affairs, Database of National Cultural Properties: Endo Family Residence Wall
- https://kunishitei.bunka.go.jp/bsys/maindetails/101/00010093
- Agency for Cultural Affairs, Database of National Cultural Properties: Endo Family Residence South Stone Storehouse
- https://kunishitei.bunka.go.jp/bsys/maindetails/101/00010090
Last verified: 2026.10.04