Hardrock 100 Aid Station Planner

The Hardrock 100 Endurance Run is a 161km loop through the San Juan Mountains of Colorado, starting and finishing in Silverton at 2,835m. The course averages 3,600m elevation, with a high point at Handies Peak (4,359m). With 10,000m of gain and loss and most of the course above treeline, it is widely considered one of the most difficult 100-mile races in the world.

Altitude is the primary challenge. Unlike other major 100-milers where heat or distance is the limiting factor, Hardrock's defining characteristic is altitude. The metabolic cost of running at 3,500-4,000m is 15-20% higher than at sea level. Pace targets calibrated to low-altitude performance will be systematically too aggressive. Use the nutrition calculator with altitude set to "high" and add an additional 10-15% time buffer to km-effort pace estimates.

Key sections. The first major climb from Silverton to the Cunningham Gulch area (1,200m D+ in 14km) is the opening statement. Ouray (42km) is the first major crew access and marks the roughly one-quarter point. The Engineer crossing (4,300m) and Grouse Gulch (74km) are the psychological midpoint. Sherman (109km) at hour 20-30 for mid-pack runners is the last major crew access before the finish.

Weather unpredictability. July in the San Juans means afternoon thunderstorm risk daily. Aid station schedules must account for mandatory lightning shelter times at exposed sections. Build buffer time throughout - weather delays are not exceptional, they are expected.

Crew access points: Ouray (42km), Grouse Gulch (74km), Sherman (109km) - and limited access at other points. The course is partially run in reverse in alternating years - check the current year's direction.

Checkpoint data approximate - verify against current official race guide at hardrock100.com before your race.