The Nez Perce name for the Joseph Creek area was an-an-a-soc-um which means "long, rough canyon," an appropriate name for the two thousand-foot-deep basalt canyon here. Like a preview of coming attractions, the view of Joseph Canyon hints at the drama of the Grande Ronde Canyon which it soon joins and which the highway will soon be descending. About fifteen miles farther down the creek was the winter camp of some families of the Wallowa band at the confluence of Joseph Creek and the Grande Ronde.
The Nez Perce Flight to Canada - An Introduction