Get The App
Race guide · California, USA
How to train for The Big Alta
Marin County's big-vert trail weekend: the Golden Gate Bridge, the Marin Headlands, Mt. Tamalpais and one steep ridge after another. Here's what to know and how to get ready.
Next race Mar 19–21, 2027
| Distance | Climb | Time limit | Start | |
|---|---|---|---|---|
| 100K | 62.5 mi | 12,750 ft | 17 h | Sat Mar 20 6:00 AM |
| 50K | 31 mi | 6,700 ft | 9 h | Fri Mar 19 7:00 AM |
| 28K | 17.4 mi | 3,900 ft | 5.5 h | Sun Mar 21 8:00 AM |
The 100K starts at Fort Baker by the Golden Gate Bridge and finishes at Marinwood Community Center; the 50K and 28K start and finish at Marinwood.
What makes it hard
Steep, all day
The 100K climbs about 12,750 ft, roughly 200 ft for every mile, and descends just as much.
Train for it: Weekly hill repeats, power hiking on steep grades, and leg strength for the descents.
Tight time limits
The 100K has 17 hours and the 50K has 9, which is less time than many races of the same distance give you.
Train for it: Long runs at race effort, and practise getting in and out of aid stations quickly.
Changeable coastal weather
Late March can bring sun, wind, fog or rain, with mornings in the 40s °F and afternoons up to the mid-70s.
Train for it: Train in whatever the weather gives you and settle your layering system early.
How long to train
Plan on 20–24 weeks for the 100K, 14–18 for the 50K and 10–12 for the 28K if you're already running 4–5 days a week. Hills every week from the start.
Get a plan built around race day
Set Big Alta as your goal race and VertPro builds your training back from the start line, then adapts week to week. A Vert.run coach reviews your plan in the first 24 hours.
Want the most hands-on option? Premium gives you unlimited chat with your coach and a monthly call.
How much elevation gain is The Big Alta?
The 100K climbs about 12,750 ft, the 50K about 6,700 ft and the 28K about 3,900 ft, each with the same amount of descent.
When is The Big Alta 2027?
March 19–21, 2027: the 50K on Friday, the 100K on Saturday and the 28K on Sunday, according to the organiser. Always confirm on the official race site.
Race facts checked October 2, 2026 against daybreakracing.com. Confirm dates and rules with the organiser. Vert.run is not affiliated with the race.