Big Thompson River

CO • US

The Big Thompson River is a tributary of the South Platte River, approximately 78 miles (126 km) long, in the U.S. state of Colorado. Originating in Forest Canyon in Rocky Mountain National Park, the river flows into Lake Estes in the town of Estes Park and then through Big Thompson Canyon. It includes four crossings/bridges which are listed on the U.S. National Register of Historic Places.

78.3 mi total 1 sections 3 access points 5 camps 0 rapids

🗺 Explore map

Click any point for details. Sections without stored geometry are drawn as straight put-in → take-out lines — actual courses follow the river.

Sections (1)

Big Thompson River upstream end (OSM) to Big Thompson River downstream end (OSM)

● Big Thompson River upstream end (OSM) → ● Big Thompson River downstream end (OSM)

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