The Rocky Mountain Arsenal National Wildlife Refuge is a former Army chemical weapons facility (coined Rocky Mountain Arsenal). Shortly after the Cold War the facility was converted into a park and wildlife refuge after a group of bald eagles was discovered on the premises. Located just 10 miles from Denver, the refuge is easily spotted on a map as the expansive green area just northeast of downtown that covers 15,000 acres. While not considered a state or national park, the refuge is managed and operated by the U.S. Fish and Wildlife Service and is classified as a National Wildlife Refuge.
Just one day in the refuge will expose you to an abundance of wildlife. On a typical day driving through the refuge, it's not uncommon to spot bison, deer, prairie dogs, bald eagles, hawks, owls, herons, and many other wildlife viewing opportunities for families, photographers, and birders alike.
There are roughly 10 miles of trails for hiking throughout the refuge, multiple picnic areas, paid fishing opportunities, and a 9-mile scenic wildlife drive within the park.