The Dolores River Canyon WSA consists of rugged canyons cut
through a series of sedimentary strata, resulting in a vertical-
walled canyon system with colorful ledges and massive cliffs.
Approximately 30 miles of the Dolores River are included in this
WSA. The numerous tributary canyons are often very narrow,
sheer-walled, and boulder-choked, leading up to hidden grotto
pools of clear, cool water with hanging ferns and other non-
desert vegetation. River elevation drops from ~5,300 to ~5,000
feet within the WSA. Benches of bedrock and rocky ridges rise
500 to 700 feet above the canyon bottom, while the rim is ~1,100
feet above the river. The geologic history of the area is
clearly exposed by the deep cutting action of the river,
offering a 160-million-year-old exhibit, beginning with the
oldest exposed rock-limestones of the Pennsylvanian Period
(formed 300 million years ago) - and progressing up to the
youngest exposed material-outcrops of the Entrada Sandstone from
the Jurassic Period (formed 140 million year