Just beyond the lowest switchback shown in figure 54, we penetrate the
Wingate Sandstone through a tunnel, the south portal of which is shown
in figure 56. After we drive through a deep cut in the Wingate Sandstone
just south of the tunnel, we cross the entire red Chinle Formation, then
descend a series of switchbacks in old Proterozoic rocks. The Chinle
Formation is crossed again near the foot of the hill, where it is about
80 feet thick,[39] then we recross the Wingate Sandstone and Kayenta
Formation to the parking area in the Devils Kitchen Picnic Area, near
the foot of the old Serpents Trail.