The Tomioka Silk Mill and Related Industrial Heritage is a group of places connected to Japan's industrial growth during the Meiji period. This heritage is part of Japan's industrial history. The Tomioka Silk Mill was built in 1872 in Gunma Prefecture, which became an important center for sericulture, the process of raising silkworms and producing raw silk. In 2007, these sites were submitted together for inclusion on the UNESCO World Heritage List under certain standards. Ten locations were proposed (listed below). In 2014, four sites were kept as part of the Tomioka Silk Mill and Related Sites.