Boulder Reservoir
‘The Rez’ to locals — a sandy-beach reservoir with a dedicated, LIFEGUARDED swim area (unusual for this region), concessions, and
lake
Boyd Lake State Park
A full-service reservoir just over an hour north of Denver with a designated swim beach, marina, and nearby camping.
Chatfield Reservoir (Chatfield State Park)
A 1,500-acre reservoir just south of Denver popular for swimming, boating, and birdwatching (200+ species recorded) — note a fatality
Cherry Creek Reservoir (Cherry Creek State Park)
A convenient, calm-water reservoir swim beach within the Denver metro area itself — one of the most accessible options without
Aurora Reservoir
One of Aurora’s largest park and open-space sites, with a sandy beach for swimming/sunbathing and an on-site education center about
Bear Creek Lake Park (Big Soda Lake)
A close-to-Denver lake within Bear Creek Lake Park offering a classic beach-day setup without a long drive.
Wellington Lake
A serene 167-acre lake near the small town of Bailey along US-285, popular for canoeing, swimming, and quiet mountain scenery.
Brainard Lake Recreation Area
One of the most accessible alpine lakes on the Front Range — literally steps from the parking lot — though
Island Acres (Colorado River)
A developed swimming and fishing area along the Colorado River near Palisade, with calmer pond sections distinct from the swifter
Grand Lake
Colorado’s largest natural lake, offering crystal-clear water, mountain scenery, and a charming lakefront downtown just outside Rocky Mountain National Park.