Goosenecks State Park
Serpentine ridge
Around Mexican Hat, the San Juan River is slow-moving and flows through a relatively shallow canyon with many wide curves; more of these convolutions can be seen in the nearby Goosenecks State Park, reached by a 4 mile paved side road (UT 316) off UT 261. The park, to which entry is free, has just one extended viewpoint of several huge river bends, now flowing one thousand feet below ground level in a deep canyon with a series of stepped cliffs and terraces; this is recognized as one of the best examples of entrenched river meanders in the world.
Goosenecks State Park is located near the southern border of the state of Utah in the western United States. It overlooks a deep meander of the San Juan River. Millions of years ago, the Monument Upwarp forced the river to carve incised meanders over 1,000 feet (305 meters) deep as the surrounding landscape slowly rose in elevation. Eroded by water, wind, frost, and gravity, this is truly a magnificent viewpoint.
Some of the text from Wikipedia
Mexican Hat