Horsetooth Reservoir
Shoreline Trail, west of Fort Collins, CO
Fort Collins, CO
A long, narrow reservoir hidden behind a rocky hogback just west of Fort Collins, with sandstone shores, sailboats, and the distinctive Horsetooth Rock above.
Horsetooth Reservoir is Fort Collins's beloved backyard lake, a long, narrow body of water tucked into the foothills just west of town, hidden behind a rugged hogback ridge so that you do not see it until you crest the rise. Nearly seven miles long and hemmed by sandstone cliffs and coves, it is a magnet for boaters, swimmers, anglers, and hikers, all within a few minutes' drive of the city.
Above the western shore rises Horsetooth Rock, the notched sandstone formation that gives the reservoir its name and serves as a landmark for the whole region. The reservoir is not a natural lake but a working part of a vast water project that carries mountain water across the Continental Divide to Colorado's Front Range, yet it has become one of the most popular recreation spots in northern Colorado, a place where a college town goes to play on the water.
What Guests Love
- A long, scenic lake minutes from town for boating and swimming
- The rugged sandstone shoreline and coves
- Hiking up to the landmark Horsetooth Rock formation
- Sunsets over the water with the foothills behind
Worth Knowing
- It is a busy summer spot, so weekends and holidays fill fast
- Water levels change through the season as the reservoir is drawn down
- Trails around the lake are exposed and sunny, so bring water
- Watch the weather; foothills storms can build quickly in summer
Details
Fort Collins, CO
Learn about Horsetooth Reservoir
Water from the other side of the mountains
Horsetooth Reservoir was created in the late 1940s as part of the Colorado-Big Thompson Project, one of the largest water-diversion systems in the West. The project captures water on the wetter western slope of the Rockies and moves it, through tunnels bored beneath the Continental Divide, to the drier eastern plains where most of the state's people and farms are. Horsetooth is one of the reservoirs that stores and distributes that water.
Dams built across gaps in the hogback ridge hold the water in the long valley behind it, which is why the reservoir has its distinctive shape, narrow and winding, following the natural trough between the ridges. What began as pure infrastructure quickly became a recreation destination, and today the water that irrigates farms and fills city taps also carries sailboats and swimmers on a summer afternoon.
The hogback and Horsetooth Rock
The reservoir sits in a striking piece of foothills geology. The long ridge that hides it from town is a hogback, a narrow spine of hard, tilted sandstone left standing after softer rock eroded away, the same kind of upended rock layers found all along the Front Range where the mountains pushed the land skyward. The reservoir fills the valley just behind this ridge.
Above the western shore rises Horsetooth Rock, a distinctive notched sandstone formation visible for miles across the plains and a favorite hiking destination. Local legend tells of a Native tale explaining the notch, and the rock has become the informal symbol of Fort Collins. A trail climbs to its base and up onto the formation for sweeping views of the reservoir, the city, and the plains beyond.
On the water and around it
In summer the reservoir comes alive with boats of every kind, from sailboats catching the foothills wind to motorboats, kayaks, and paddleboards, and swimmers cool off at its beaches and coves. Anglers fish its waters for bass, walleye, trout, and more, and campgrounds and picnic areas line the shore. It is the closest real water recreation to Fort Collins, and it shows on a hot weekend.
Around the lake, a network of foothills trails threads through the sandstone and open space, from the shoreline paths to the climb up Horsetooth Rock and the trails of the adjacent open spaces. The mix of water and rugged foothills terrain makes the area a year-round draw, with hiking and mountain biking in the cooler seasons when the boating slows down.
Fort Collins below
Just down the hill lies Fort Collins, one of the most livable towns on the Front Range, a college city anchored by Colorado State University with a walkable, brick-lined Old Town of shops, cafes, and breweries. The reservoir is close enough that residents slip up for an evening paddle or a sunset hike after work, and visitors can easily pair a day on the water with a night downtown.
The wider region opens out from here into the northern Front Range, with the Cache la Poudre River canyon, Rocky Mountain National Park, and the high country all within reach. Horsetooth Reservoir makes a natural centerpiece for time around Fort Collins, a scenic lake with a view of the mountains and the plains at once.
Closest Boutels
The closest Boutel™ stays, so you can turn this stop into an overnight. Each is an independently owned, editorially selected place to stay.
Things to Do Near Fort Collins
Fort Collins
About 5 miles east
A lively college town with a walkable Old Town of shops, cafes, and breweries at the foot of the foothills.
Horsetooth Rock
Above the western shore
The notched sandstone landmark that names the reservoir, reached by a hike with sweeping views.
Lory State Park
About 10 miles west
A foothills park along the reservoir's western shore, with trails through sandstone canyons and meadows.
Cache la Poudre River Canyon
About 15 miles northwest
Colorado's only Wild and Scenic river, tumbling out of a dramatic canyon with fishing, rafting, and drives.