In 1872, barely four years after the Meiji Restoration had ended the rule of the shoguns, Japan's new government opened a model silk-reeling mill in the small town of Tomioka in Gunma prefecture. It hired a French engineer, Paul Brunat, imported French machinery, and recruited young women from across the country to learn the new techniques and take them home. The long brick buildings, a curious mix of Japanese timber framing and European brick, still stand, and the mill operated until 1987. In 2014 it was inscribed on the UNESCO list together with related sericulture sites, such as farms where silkworm rearing methods were improved and a cold storage cave used to control the hatching of eggs.
Silk was Japan's great export in the late nineteenth and early twentieth centuries, paying for the country's modernisation, and Gunma was at the heart of the industry. Many old farmhouses in the area have distinctive raised roofs with ventilation sections built for raising silkworms in the attic. The mill tour explains the process, from cocoon to thread, and the scale of the buildings gives a sense of the ambition of the early Meiji state.
The riding around Tomioka is a pleasant mix of valley and mountain. The town sits in the Kabura river valley on the edge of the Kanto plain, with the strange, jagged peaks of Mount Myogi rising to the west. The Myogi area has some excellent twisty roads, climbing through forest with tight corners and great views of the rock pinnacles. Further west, the road toward Karuizawa and the Usui pass climbs into the mountains, with famous hairpins on the old pass road. Traffic on weekends can be heavy, and summer is hot and humid, but spring and autumn are lovely.
Tomioka has around fifty thousand inhabitants, with fuel stations, convenience stores and restaurants. Look out for local specialities such as konnyaku, made from the root of a plant grown in Gunma, and hearty udon noodles. The mill is right in the town, with paid parking nearby; plan for at least an hour to walk around the buildings and see the reeling machines. Then head for Myogi in the afternoon for a ride through the pinnacles before the light goes.