Dale Furnace and Forge Historic District preserves an early Pennsylvania iron plantation in Washington Township as both a building complex and an archaeological site. Centered on a stone furnace stack built about 1791, with forge foundations and a water race dating from roughly 1804 to 1811, the property traces iron production from the late 18th century into the industrial 19th. The furnace operated until about 1822, and Dale Forge until 1868. Its six contributing buildings and one contributing site include the ironmaster's mansion, counting house, worker's house, barns, smokehouse, and wash house, together showing how industrial, farm, and household life were closely linked.