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Horsetooth Open Water Swim

Horsetooth Open Water Swim took place on Sun, Sep 13, 2026 in Fort Collins, United States. The main route is 10 km.

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Date
Sun, Sep 13, 2026
Start
Fort Collins 🇺🇸
Distance
10 km
Level
Open to all

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The Horsetooth Open Water Swim is a high-altitude open water event held at 5,430 feet in the Horsetooth Reservoir in Fort Collins, Colorado.

What this race demands

The Horsetooth Open Water Swim demands sustained high-altitude aerobic endurance across a 10 km open water distance.

Altitude adaptation

Athletes must manage the physiological stress of competing at an elevation of 5,430 feet in Fort Collins, Colorado.

Endurance capacity

The 10 km swimming distance requires advanced pacing strategies and extensive physical durability to sustain effort over an extended duration.

Open water navigation

Participants must maintain efficient sighting and stroke mechanics in a reservoir environment without lane lines.

Given the extended duration of a 10 km swim, athletes should target 60 to 90 grams of carbohydrates per hour through liquid or easily digestible nutrition managed via support craft or feed stations.

Frequently asked questions

When is Horsetooth Open Water Swim?

Horsetooth Open Water Swim took place on Sun, Sep 13, 2026 in Fort Collins, United States.

How long is Horsetooth Open Water Swim?

The main route is 10 km.

What does Horsetooth Open Water Swim demand?

The Horsetooth Open Water Swim demands sustained high-altitude aerobic endurance across a 10 km open water distance.

Who is Horsetooth Open Water Swim for?

Horsetooth Open Water Swim is open to all participants.

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