This is Castle Gardens.  It is off the beaten path, but well worth the visit.  The petroglyphs are really amazing!

The Castle Gardens Petroglyph Site is located in central Wyoming approximately 45 miles east of Riverton. The name of the area comes from the outcropping of sandstone which the wind has eroded into fanciful shapes resembling the turrets and towers of castle. This unusual formation has been luring visitors for thousands of years, and many of them left their mark in the soft sandstone–the area holds a treasure of Native American rock art, or petroglyphs.

Contact Information: http://www.blm.gov/wy/st/en/field_offices/Lander/cultural/castlegardens.html
BLM Worland Field Office, Worland WY 82401
(P) 307-347-5133 (E) Jeff_J_Johnson@blm.gov
This information came from: www.wyomingtourism.org