Why we love it: Absolute convenience; it is practically in our backyard.

When to go: Commerce City’s Rocky Mountain Arsenal is rarely crowded, but if you go early—the area opens at sunrise—you’ll have the best odds for bird and wildlife watching.

When you look out over the Rocky Mountain Arsenal National Wildlife Refuge’s waving prairie grasses, it is hard to imagine that this area was once a vital part of the country’s World War II and Cold War efforts. What is now home to prairie dogs and a herd of bison was once a spot for manufacturing napalm, mustard gas, and white phosphorus. (Not creeped out yet? The site also stocked sarin gas.)

In the 1980s, contamination from the production of those chemicals helped land the Arsenal on the country’s “Superfund” list, which is a way to monitor and mitigate hazardous waste sites. When a group of bald eagles was found nesting there in 1986, though, efforts to turn the site back into an environmental safe zone intensified. (At that time, bald eagles were a threatened and endangered species.) It took more than 20 years, but in 2011, a 27-square-mile area was officially declared cleaned up.

All of which means we have an urban wildlife refuge just about 10 miles from downtown—with an interesting past. If you spend the day there, first take some time to explore by car, making sure to cruise through Wildlife Drive, a nine-mile stretch that goes by the Visitor Center. After that, head to the Lake Mary and Lake Ladora loops (0.6 and 1.8 miles, respectively) for some easy hiking. This area was hit hard during the 2013 floods, so some trails are still washed out, but it is easy to follow the detours and stay on dry land (yes, some of the areas are still wet).

You’ll find plenty of anglers casting at Lake Mary via an extensive floating wooden boardwalk (the nearby cattails are an ideal background for a selfie). Picnickers should continue on to Lake Ladora, where massive cottonwoods shade the banks. The entire walk is pretty flat, which makes it ideal for letting a little one loose. Stroller-pushers beware: We’ve blown two BOB tires after picking up thorny spikes on the trail; opt for a backpack walk instead.

Getting there: Hop on I-70 east to the Quebec Street exit. Turn north and drive on Quebec Street for 1.3 miles before taking a right on East 60th Avenue. Drive 0.4 miles and turn left on Trenton Street. Cross Prairie Parkway into the Arsenal.

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Natasha Gardner
Natasha Gardner
Natasha Gardner is a Denver-based writer and the former Articles Editor for 5280.