Longmont Dam Road Access provides walk-in only access to Button Rock Preserve along North Saint Vrain Creek, with a parking area located at County Road 80 near Lyons, Colorado.

The preserve offers creek access for fly fishing and hiking trails, with a fully accessible creekside fishing pier located just past the entrance gate.

The parking lot operates from one hour before sunset to one hour after sunset daily, and the northwest corner is seasonally closed December 1 through March 31 to protect winter elk habitat.