Fortress Cliff (14).—
The Ogallala [Formation] of [Pliocene] age ([p. 23]) forms the upper rim of the canyon and is well exposed in impressive Fortress Cliff ([fig. 33]). Although this precipitous cliff dominates the eastern rim of the canyon along most of the scenic drive, especially good views are afforded between the second and third water crossings.
The [Rock] Garden (15).—
Shortly after fording the river at the fifth water crossing, there is a jumbled pile of boulders on the west side of the road ([fig. 34]). This accumulation of Trujillo [sandstone] blocks has been named the [Rock] Garden. Many boulders such as these have accumulated on the floor of the canyon in ages past. However, most of these have been destroyed by [weathering] and their fragments removed by the canyon’s streams.
The Devil’s Slide (16).—
The Devil’s Slide can be reached by an unimproved road that leads southwest from the scenic drive for a distance of about half a mile. Composed of upper Quartermaster and lower Tecovas [shales], the surface of this eroded spur is laced with many trails and “slides” that have been made by previous visitors ([fig. 35]).
Fig. 31. The Lighthouse, an erosional remnant and the “trademark” of Palo Duro Canyon, exhibits well the geologic phenomenon of differential erosion ([p. 31]).
The Turnaround (17).—
A loop marks the end of Park Road 5 and the conclusion of the scenic drive. Located in this area are a number of fine camping areas, picnic grounds, the old stone cottages called the “Cow Cabins,” and rest rooms with shower facilities ([fig. 36]).