Hebgen Lake is a reservoir created by the Hebgen Dam, located in Gallatin County in southwest Montana. It is well known for the 1959 Hebgen Lake earthquake (magnitude 7.1 to 7.5) which occurred nearby on August 17, 1959, forming Quake Lake, which is located immediately downstream.

In addition to the Madison River, which flows through the reservoir, the tributaries include the South Fork Madison River, which feeds the southeastern Madison Arm, as well as Duck Creek, Grayling Creek and Red Canyon Creek, which flow into the eastern Grayling Arm. To the west, opposite the Grayling Arm, Watkins Creek flows into the main part of the reservoir.

Hebgen Lake and the surrounding area offer many recreational activities: camping, fishing, boating, and hiking. Campgrounds include Rainbow Point and Cherry Creek. Rainbow Point is the largest campground on the lake, offering four "loops." Each loop contains approximately 20 campsites. Each campsite can accommodate a full-size camper and one or two vehicles.

• Firehole Ranch
• Quake Lake
• Yellowstone Caldera

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  Hebgen Lake, Montana with a mountain as a backdrop
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  Madison Arm, looking towards Cherry Creek Campground
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  Hebgen Lake, looking North from Rainbow Point Campground
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  Cabin partially submerged by 1959 earthquake

• Hebgen Lake Bathymetric Map Archived 2020-07-14 at the Wayback Machine Montana Fish, Wildlife & Parks