The Rocky Mountain Greenway Trail is a regional trail across the northern part of the Denver metropolitan area to connect the Rocky Mountain Arsenal National Wildlife Refuge in Commerce City to the Rocky Flats National Wildlife Refuge, which directly abuts Westminster’s western boundary at Indiana Street. This trail was named one of the "16 in 2016" trail projects in Colorado by Governor Hickenlooper. The City has partnered with the Federal Highway Administration to construct the trail in Arvada, Westminster, and Broomfield.

Much of the trail utilizes existing regional trails, such as the Sand Creek Trail, South Platte Trail, Clear Creek Trail, and Little Dry Creek Trail. The trail passes through two parts of Westminster. The Little Dry Creek Trail section of the Greenway Trail will cross through south Westminster. For a detailed description of this trail segment, see the description of the Little Dry Creek Trail.  The trail also passes through Westminster, north of 86th Parkway and east of Indiana Street, across Standley Lake Regional Park and Westminster Hills Open Space. The trail crosses under 86th Parkway just west of Kipling Street along the Farmers’ High Line Canal. The trail hugs the east side of Standley Lake along the base of the Standley Lake dam. The Greenway Trail uses the Big Dry Creek Trail along the east and north side of Standley Lake to Simms Street.  West of Simms Street, the trail runs south of the Standley Lake Regional Park Nature Center and crosses 100th Avenue onto the Westminster Hills Open Space. The trail continues in a northwesterly alignment to about 108th Avenue and Indiana Street.

Subsequent phases will cross Indiana Street, extend the trail onto the Rocky Flats National Wildlife Refuge and eventually to Boulder and perhaps Rocky Mountain National Park.