Closed for years because of rock-fall hazard, the Aspen Trail was built in the 1960's by Navajo stoneworkers. The final segment is cut from the face of a slightly overhanging cliff, with no railing or wall and a sheer drop of hundreds of feet into the canyon bottom. Dine (Navajo) ranger-guide Bill Little leads groups (maximum size 15) down the cliff trail then up to the Betatakin Ruin in the alcove on the other side.