Horseshoe Park is a valley in Rocky Mountain NP and is famous for wildlife viewing. Bighorn sheep visits Sheep Lakes in late spring and early summer, and elk is frequently seen in the area. Little Horseshoe Park Overlook has a great view of the valley.
My husband and I visited the area around 7pm in late August. Although we didn't see any sheep (as it wasn't the right time of year), we were lucky enough to see wild turkey, elk, and black bear while driving on Fall River Road. View from the overlook was wonderful.