Hardrock 100 course

Location
Colorado, USA
Event Timing
Early July Annually
Organiser
Hardrock Hundred Endurance Run
Official site
hardrock100.com
Looped courseVery mountainousVery high altitudeTechnical

Hardrock 100 course key stats

Distance
101.8 miles163.8 km 163.8 km101.8 miles
Ascent
+33,450 ft+10,190 m +10,190 m+33,450 ft
Descent
−33,450 ft−10,190 m −10,190 m−33,450 ft
Surface
99.5% Trail
0.5% Road

Source: The distance and the ascent are from the race organiser (hardrock100.com). We calculate the descent from the organiser ascent and the elevation difference between the start and the finish. The elevation profile and the gradient data come from a 10 m digital elevation model (NED (US)). All elevations are to the nearest 10 m (50 ft).

Hardrock 100 interactive course map

Looped courseVery mountainousVery high altitudeTechnical

Scroll and zoom to navigate the course below, or use the mini profile to jump straight to a specific segment. Hover a checkpoint for its distance and details, and use the controls to change the profile line colour, switch base maps, or toggle between the map and elevation views.

Race organiser? Get a course visualiser for your event site.

Our course visualiser shows a section-by-section breakdown of the Hardrock 100 course. This map shows vertical profile, maps, course surface, aid station locations and details.

All data should be considered indicative and should be checked against the official Hardrock Endurance Run race website .

About the course

The Hardrock 100 is a c.100 mi161 km ultramarathon that loops through the San Juan Mountains of southwestern Colorado, starting and finishing in the small mining town of Silverton and passing through Ouray, Telluride, and Lake City. The route alternates direction clockwise and counterclockwise each year. The interactive map above shows the clockwise route used in 2026.

It is renowned as one of the toughest courses in ultrarunning, climbing and descending roughly 33,000 ft10,060 m of elevation gain and loss on rugged, high-altitude trails that spend much of their length above 12,000 ft3,660 m, including a crossing of Handies Peak near 14,000 ft4,270 m.

Runners must contend with thin air, unpredictable mountain weather, stream crossings, and remote, exposed terrain far from aid stations.

Hardrock 100 course elevation

Average 329 ft62 m gain per milekm

The Hardrock 100 course ascends and descends 33,000 ft10,060 m of elevation over a series of nine mountain passes over its 100 mi161 km distance. The course has a similar elevation gain per mile to that of UTMB, but has less elevation gain compared with other alpine races such as Tor des Géants.

Hardrock 100 elevation profile

Ascent & descent analysis

Ascent Descent
% of race 9.2% 0%
0%10%20%30%40%50%+

Gradient

Hardrock 100 course altitude statistics

Average altitude 3,360 m11,000 ft

The Hardrock 100 starts in Silverton at roughly 9,300 ft2,830 m and climbs as high as 14,000 ft4,270 m at Handies Peak, meaning runners spend most of the race at altitudes where oxygen is noticeably thinner.

This persistent high elevation makes altitude acclimatisation a major factor, contributing to fatigue, breathlessness, and altitude sickness risk in ways that shape pacing and preparation far more than most ultra marathons.

Altitude bands and performance impact

% of race 11% 0%
VO2max decline
0m0ft 500m1,640ft 1,000m3,281ft 1,500m4,921ft 2,000m6,562ft 2,500m8,202ft 3,000m9,843ft 3,500m11,483ft 4,234m13,891ft

Altitude

VO2max decline 30% 0%
Negligible Low Moderate High Very high VO2max decline

Hardrock 100 course weather conditions

Wide temperature range Sub-freezing conditions possible: record low -7.1°C19°F

In mid-July, the San Juan Mountains bring a mix of intense high-altitude sun during the day, cold temperatures overnight, often dropping near or below freezing at the higher elevations.

The classic Colorado monsoon pattern of afternoon thunderstorms can bring heavy rain, hail, lightning, and sudden temperature drops, especially dangerous on the exposed above-treeline sections.

The weather data has been obtained using the Open-Meteo historical weather API.

Conditions at the start line

The pictograms below show the conditions at the start of the course on the race date in each of the last five years.

2022
11°–22°C51°–71°F
💨 10 km/h6 mph
💧 1.6 mm0.06 in
2023
10°–21°C51°–69°F
💨 22 km/h13 mph
💧 0 mm0.00 in
2024
5°–22°C41°–72°F
💨 12 km/h8 mph
💧 1.3 mm0.05 in
2025
10°–22°C50°–72°F
💨 20 km/h12 mph
💧 0.7 mm0.03 in
2026
5°–23°C40°–73°F
💨 15 km/h9 mph
💧 0.1 mm0.00 in

Temperature range on course

Temperatures experienced on course are impacted by elevation. The graph below shows the temperature range for the five most recent events at different parts of the course.

Start 9,300 ft 2,840 m
-10°C14°F 35°C95°F
2°C35°F 7–21°C45–70°F 27°C81°F
High point 14,050 ft 4,280 m
-10°C14°F 35°C95°F
-7°C19°F 1–11°C33–53°F 17°C62°F
Avg. 8°C15°F colder
Low point 7,700 ft 2,340 m
-10°C14°F 35°C95°F
7°C45°F 12–26°C54–78°F 31°C88°F
Avg. 5°C9°F hotter
Typical (5-year average) Recorded extremes

Daylight hours

The graph below shows the daylight hours on the day of the 2026 edition (10 July), in local time.

14.6 hrs daylight

00:00 24:00
Sunrise: 05:57 Sunset: 20:34