St. Paul and Minneapolis jointly form the Twin Cities, but St. Paul is the state capital and very different in character from Minneapolis. St. Paul is spaciously laid out, built on terraces above the Mississippi, with more of an old frontier town atmosphere. It began as a military post, established in 1807 at the junction of the Minnesota and Mississippi Rivers, and later became Fort Snelling. This port soon became a major stop for river boats, and the area quickly grew into a major center for fur traders and other commerce. St. Pauls crowning jewel is the Cathedral of St. Paul, which overlooks the downtown area, and the impressive Golden Age mansions of Summit Avenue add to the citys architectural grandeur. St. Paul is packed with historic attractions, including the opulent James J. Hill House, the reconstructed grounds of Fort Snelling, and the Gibbs Museum, a living history farm.