Sinks Canyon State Park
I took this photo of the Sinks in Sinks Canyon State Park in the Wind River Mountains of Wyoming.
The Popo Agie River actually disappears (sinks) into the canyon mouth and reappears about a quarter mile down the canyon. This is a fascinating phenomenon in the magnificent Wind River Mountains. It's been said that Louis L'Amour considered these mountains his favorites.
(I was a bit confused when I first heard of Sinks Canyon. The term "sinks" was the name used for the latrines on frontier forts.)