Marin Ultra Challenge 50 Miler — 2027 — Course Map, Elevation Profile & Aid Stations

Course map, elevation profile & surface

Distance

49.0mi

Elev gain

12,795ft

Elev loss

12,795ft

High point

1,827ft

Low point

16ft

Surface

62% trail

Drawing the course…

The course file didn’t load.Usually a hiccup. The stats above are still right.

Race-day light

In the dark

Sunrise

6:26am

Sunset

6:16pm

Headlamp from

Not needed

For a 11:10 finish (an estimate) · starting 7:00 AM Mar 13. Dark means the sun below civil twilight.

Climbs

12 climbs · 8,904 ft totalbiggest first

Pick a climb to find it on the profile and the map.

Elevation gain, measured two ways

Source	Gain	vs lidar
Course file (GPX)	12,795ft	+28%
USGS lidar, 1 m	9,980ft	reference

They differ because a GPS file picks up noise on every wiggle and often takes its heights from a coarse terrain model, while lidar maps the ground itself to about a metre. We sampled this route every 98 ft against USGS 3DEP and counted each rise of 10 ft or more, on Oct 25, 2026. The planner still uses the course file.

Conditions typical race-day weather for Mar 13 at the start

Typical high

59°F

Typical low

46°F

Chance of rain

44%

2025 high

53°F

Typical = the median of 2016–2025 for Mar 13 ±3 days at the start line; a wet day has 1 mm of rain or more. Historical weather from Open-Meteo.

Race almanac the sky on race day

Next race day Sat, Mar 13, 2027 · 7:00 AM start

First lightsunrise 6:26 am

5:59am

Last lightsunset 6:16 pm

6:42pm

Moonwaxing crescent, up until 12:26 am

35% lit

First and last light are civil twilight, the sun 6° below the horizon. The moon is lit as at midnight after the start; headlamp hours count a typical finish from the start while the sun is below civil twilight. Worked out for the start line.

Reviews what runners who have been there say

No reviews yet — be the first to run it and tell other runners what to expect.

About this course

Marin Ultra Challenge 50 Miler — 2027 covers 49.0 mi (78.9 km) with 12,795 ft of elevation gain. That is about 261 ft per mile of climbing, and 12,795 ft of descent. The course tops out at 1,827 ft and bottoms out at 16 ft. The surface is 62% trail, 29% gravel and 8% paved. The profile has 12 sustained climbs; the biggest is the climb from mi 22.4, +1,781 ft over 2.5 mi at 13.5% on average (steepest stretch 30%). Race day is March 13, 2027, starting at 7:00 AM; the sun rises at 6:26 AM and sets at 6:16 PM. Typical race-day weather at the start: a high of 59°F and a low of 46°F, with a 44% chance of a wet day. The interactive map above shows the full route with its elevation profile and aid stations, built from the course's GPS file.

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