Tomioka Silk Mill

Tomioka opened in 1872 as the country's first mechanised silk reeling factory, built to a French engineer's plan with local materials: a timber frame filled in with brick, laid by carpenters who had never handled brick before and improvised their own bonding. The result is a long low complex of cocoon warehouses and a reeling hall roofed in one clear span, lit by continuous windows because the work needed daylight. It ran, with changing machinery, until 1987, and was then simply kept - locked, maintained and left. That is why it survives so completely, down to the last generation of reeling machines standing in rows where they stopped.

What you actually see

• The reeling hall - one long unbroken span under timber trusses, machines still in place under the windows.
• The cocoon warehouses - brick and timber facades with the founding year set into the keystone arch.
• The French-quarter buildings - the residences built for the foreign engineers, in a hybrid colonial style.
• The construction method - timber frame packed with brick, a technique invented on site out of necessity.

When to go

Any day of the year works, though the halls are unheated and cold in winter and stuffy in August. Guided tours run at set times and are the difference between a walk through empty rooms and an understanding of what happened here. Weekday mornings are close to empty. The site closes one day a month for maintenance, so check first.

Honest expectations

This is industrial history and it looks it: long brick sheds, machinery, and a lot of reading. Panels are mainly in Japanese with shorter English summaries, so without the audio guide much of it passes you by. Children tire of it quickly. Tomioka is a plain town on a branch line, an hour and a half out of Tokyo each way for a two-hour visit.

Nearby

The Joshin line continues into the Gunma hills; Kusatsu and Ikaho hot spring towns lie further north.