Devil's Gate, a fissure in the mountains of what is now Natrona County, Wyoming, caused by erosion from the Sweetwater River. It was a noted landmark along the Oregon Trail (and California Trail, Mormon Trail, and Pony Express route that followed the same path before diverging farther west). While it gave no particular directional guidance, emigrants -- who were walking or riding alongside, not through, the gap carrying the river -- frequently stopped to hike around this feature and carve their names. The occurrence of several murders in this region led some emigrants to believe this was a bedeviled site. Photo by Carol Highsmith.