This installation in Utah is entitled "Chase at Split Rock".

"The Mustangs” features five equestrian statues that encircle the Snow Canyon Roundabout in Ivins, Utah.
The five mustangs, one featuring a rider, are placed around the large rocks in the center of the circle near the east entrance to Ivins, allowing visitors and passersby to see the work in a continuous loop.
Hlavka says the challenge of sculpting horses in full locomotion and in the round was the most exciting and interesting aspect of this work.
Typically there is a front, back or strong side to any given figurative sculpture but in this case all five horses had to be strong from every direction.
For inspiration Hlavka drew on his respect for indigenous Ute and Paiute Tribes and his love for the speed and beauty of the wild mustangs of the American West.
For technical knowledge the longtime student of the human form drew on experiences from his youth spent on a ranch in South Dakota, the hours he spent working with his grandfather, a skilled horseman, as well as more recent studies from life and photographs.