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Union Reservoir Park, formerly known as Calkins Lake, is a 736-acre natural reservoir in Longmont that serves as one of the state's few remaining natural lakes, adapted for use as a reservoir in 1903 as a result of drilling by the Union Ditch Company to release lake water into the nearby St. Vrain Creek. The reservoir, which is located approximately seven miles from Interstate 25, is a popular destination for year-round outdoor recreational activities, including boating, windsurfing, paddleboarding, and kayaking. The reservoir is also home to a seasonal swimming beach and the Union Sailing Club, one of Colorado's largest racing sailing clubs. Anglers can fish for walleye, trout, crappie, catfish, and bass at one of the state's finest fishing spots. Day-use picnic facilities offer tables and grills, while a variety of special events bring triathletes, boaters, and community festival attendees to the park throughout the year.

461 County Road 26, Longmont, CO 80504, Phone: 303-772-1265

Rating: ⭐⭐⭐⭐⭐

Stephen Day Park Longmont Museum and Cultural Center Ron Stewart Preserve at Rabbit Mountain Sunflower Farm Wibby Brewing The Dougherty Museum St. Vrain State Park Union Reservoir Park 300 Suns Brewing St. Vrain Cidery Roosevelt Park Sandstone Ranch Park Longtucky Spirits D'Barn Reception Hall The Agricultural Heritage Center Ya Ya Farm and Orchard Firehouse Art Center BrewHop Trolley Mile-Hi-Skydiving Dry Land Distillers Lucile's Creole Cafe Mike O'Shays Restaurant and Ale Martini's Bistro Left Hand Brewing Company

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