Hellgate Canyon, a river-carved passage along the Clark Fork east of Missoula, has been important both in Native history and regional travel. Its English name grew from memory of an ambush in which the Séliš and Ql̓ispé, or Flathead, were defeated by the Niitsítapi, or Blackfeet; in Blackfoot, Iitassiimoo means “where we ambushed the enemy.” In the 19th century the canyon became a major transportation corridor, used by Lewis and Clark, the Mullan Road, and later the Northern Pacific and Milwaukee railroads. Its landscape also entered travel writing, and part of its railroad route survives today as the Kim Williams Trail.