Rocky Mt Arsenal National Wildlife 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.


Prior to becoming a Refuge, Plains Indians followed large herds of bison and lived off the land. Later, as settlers moved west to start a new life, they began growing crops and grazing cattle. Following the attack on Pearl Harbor, the U.S. Army transformed the area into a chemical weapons manufacturing facility called the Rocky Mountain Arsenal to support World War II. As production declined at war’s end, a portion of the idle facilities were leased to Shell Chemical Co. for the production of agricultural chemicals. The Arsenal was later used for Cold-War weapons production and demilitarization.

Transition to a National Wildlife Refuge

In the early 1980s, the Army and Shell began an extensive environmental cleanup under the oversight of federal, state, and local regulatory agencies. Soon after, a roost of bald eagles was discovered prompting the U.S. Fish and Wildlife Service to become involved in managing wildlife at the site. The discovery also led Congress to designate the site as a national wildlife refuge in 1992. In the mid-1990s, a unique public-private partnership formed among the U.S. Army, Shell Oil Co., and the U.S. Fish and Wildlife Service. As cleanup progressed and projects met federal and state regulatory requirements, the Army transferred land to the U.S. Fish and Wildlife Service to establish and expand the Refuge. The Arsenal’s cleanup program was completed in 2010 and the Refuge has reached its final size of 15,000 acres making it one of the largest urban refuge’s in the country.

The US FWS has undertaken a major effort to restore the RMANWR to native short-grass and mixed-grass prairie, wetlands, and woodlands. Please follow the link to learn more about the RMANWR Habitat Management Plan, which details current activities to restore the wildlife and birds to the Refuge.

Refuge Opportunities

The Refuge provides environmental education and interpretive programs, catch-and-release recreational fee fishing, 10 miles of hiking trails, wildlife viewing opportunities, site tours for the public, a self-guided Wildlife Drive auto tour, and is a sanctuary for more than 330 species of animals, including bison, deer, coyotes, bald eagles and burrowing owls. For more information about the Refuge please call the Visitor Center at 303-289-0930.

Rocky Mountain Arsenal National Wildlife Refuge website