Etna Furnace, also known as Mount Etna Furnace, Aetna Furnace, and Aetna Iron Works, is a historic iron furnace complex and national historic district located at Catharine Township, Blair County, Pennsylvania. The district includes five contributing buildings, six contributing sites, and two contributing structures.
It encompasses a community developed around an iron furnace starting in 1805. Included in the district is the four-sided stone furnace (1808), gristmill site (c. 1793), canal locks (c. 1832), site of lock keeper's house (c. 1832), aqueduct (c. 1832, rebuilt 1848), two small houses, the ruins of a charcoal house, the foundation of a tally house, a blacksmith shop, bank barn, foundation of a boarding house, three family tenant house, two iron master' mansions (one destroyed), a store and paymaster's office, Methodist / Episcopal Church, and cemetery with graves dating between 1832 and 1859.