The Österby forge complex is considered the oldest and best-preserved "forge village" in the country. A simple smelting furnace was already in operation here in 1443, however the foundry expanded rapidly following the purchase of the estate by Louis de Geer (1643). The working conditions of the time are depicted in the Walloon forge, the last of its kind. The manor house is used as an exhibition centre in summer. The grounds were designed by Carl Hårleman. The former warehouses and stables are now occupied by craft shops.