09/09/2014 10:00 AM EDT
Photographer Rich Keen captured a tender moment between a bison & calf at the Rocky Mountain Arsenal Refuge.
Located just northeast of Denver, the Rocky Mountain Arsenal National Wildlife Refuge is a 15,000-acre expanse of prairie, wetland and woodland habitat. The land has a unique story – it has survived the test of time and transitioned from farmland, to war-time manufacturing site, to wildlife sanctuary. It may be one of the finest conservation success stories in history and a place where wildlife thrives.