Lakes / Colorado / Larimer County / Horsetooth Reservoir
Horsetooth Reservoir, Colorado
1,817 acres
Surface Area
Where It Sits, and How Deep It Goes
Locator - Colorado
40.56 degrees N, 105.16 degrees W - Larimer County. State and county outlines drawn from Census boundary data; the lake marker is placed by its USGS National Hydrography Dataset coordinates, not by eye. Schematic - not a survey map.
How Horsetooth Reservoir Stacks Up
- Larger than 96% of the 778 lakes counted in Colorado.
- The largest lake in Larimer County among those counted.
- About 38 miles from Boulder, as the crow flies.
Lakes Nearby
| Lake | County | Distance | Surface Area |
|---|---|---|---|
| Dixon Reservoir | Larimer | 1.1 mi | 50 acres |
| College Lake | Larimer | 1.6 mi | 66 acres |
| Claymore Lake | Larimer | 3.9 mi | 74 acres |
| Warren Lake | Larimer | 5.5 mi | 142 acres |
| Watson Lake | Larimer | 5.5 mi | 38 acres |
| Nelson Reservoir | Larimer | 5.9 mi | 36 acres |
Straight-line distance between lake centers.
Facts and Figures
Questions About Horsetooth Reservoir
How Big Is Horsetooth Reservoir?
Horsetooth Reservoir covers 1,817 acres in Larimer County, Colorado.
What Is the Largest Lake in Larimer County?
Horsetooth Reservoir is the largest lake in Larimer County, at 1,817 acres.
Largest Lakes in Colorado
| # | Lake | County | Surface Area | Max Depth |
|---|---|---|---|---|
| 1 | John Martin Reservoir | Bent | 11,686 acres | - |
| 2 | Blue Mesa Reservoir | Gunnison | 8,944 acres | - |
| 3 | Lake Granby | Grand | 7,075 acres | - |
| 4 | Lake Meredith | Crowley | 5,539 acres | - |
| 5 | Adobe Creek Reservoir | Bent | 4,770 acres | - |
All 778 Colorado lakes ranked by surface area
Sources: USGS NHD (The National Map NHD MapServer layer 12) named waterbodies FTYPE 390/436; counties via Census point-in-polygon lake data (ID 128076370). Verified October 30, 2026.