Mt. Tamalpais is the dominating feature in Marin County. Any true trail runner who sees it wants to run up it. Here’s your chance. Our Mt. Tam Trail Run begins at Stinson Beach and climbs (and climbs!) to perched views from Tam before returning via some of the best trails the Headlands have to offer until reaching the beach and bountiful post race food. Bring the family and enjoy an afternoon with friends in the sand and surf.
Location: Stinson Beach, CA
NEW FOR 2023 50K PRIZE PURSE
Female and Male Top 3 overall.
1st - $300, 2nd $200, 3rd $100.
Date:Saturday, November 11, 2023
Events:10K, Half Marathon, 30K, 50K
Friday Bib Pick-up:SF Running Company Mill Valley 12:00 PM - 6:00 PM
Saturday Bib Pick-up and Check-in: 6:30 AM – 8:00 AM
10K - 8:00 AM
Half Marathon - 8:00 AM
30K - 7:30 AM
50K - 7:30 AM
Time Limit: There is an 8.5 hour time limit for the 50K race
Parking: Parking is available within the Stinson Beach Day Use Area and is free of charge. Carpooling is always strongly encouraged.
Race Capacity: The Mt. Tam Trail Run will have a capacity of 500 runners, across all distances.
Detailed Course Map | Turn by Turn Directions | Aid Station Distances and Cutoffs | Elevation Profiles
Inside Trail Racing aid stations are replete with an optimal variety of glycogen-replenishing, electrolyte-replacing products. The following is a list of some of the foods and beverages each aid station may provide: Gu Energy gels, chews, and Stroopwafels, trail mix, pretzels, potato chips, Oreo cookies, Coke, Mountain Dew, Ginger Ale, water, Skratch Labs Sports Hydration Mix, PB&J sandwiches, M&M’s, salt tablets, bananas, watermelon, and tangerines. Aid stations are also equipped with general first aid items, including Salt-Stick tablets, but no anti-inflammatory medicine.
Skratch Labs is 80 calories per serving with minimal sugar (4g per 100 ml) and a ratio of sugar (glucose + fructose) that is optimized for faster absorption, an electrolyte profile that actually matches what is lost in sweat (800 mg sodium, 80 mg potassium, 100 mg calcium, and 80 mg of magnesium per liter)
As distances between aid station vary, we strongly encourage all runners to carry at least one 20oz bottle during their run.
Without the support of enthusiastic and caring volunteers producing our races would not be possible. Volunteers of all ages and abilities help with setup, check-in, aid stations, course marshaling, timing, and post-race food.
Volunteering is a fun, novel way to experience races, play in the outdoors, and spend time with friendly people. All volunteers receive a free race T-shirt, free food, and the ability to earn credit toward a future Inside Trail Racing event, commensurate to the amount of time worked.
To volunteer for this year’s event, please submit our online volunteer form.
All registered runners will receive a District Perfect-Tri tri-blend fabric shirt. This tee is made with top-of-the-line sportswear technology to heighten performance during your toughest workouts. With sun defense, moisture-wicking technology, quick stain release, and comfortable fit, this tri-blend performance crew serves the needs of every athlete. It’s the perfect year-round choice for outdoor sports and exercise. Get the most out of your workout with this tough, hardworking tee.
● 4.5-ounce, 50/25/25 poly/combed ring spun cotton/rayon, 32 singles
● 1X1 rib knit neck
● Shoulder to shoulder taping
● UPF 30
To be guaranteed your shirt size, you must register by October 28, 2023.
The top three overall winners (male and female) of each race distance will receive a custom trophy with the race logo. In addition, the top finisher for each distance (male and female) will receive a special item from one of Inside Trail’s sponsors.
All finishers will receive a custom medal with the race logo.
All 50K finishers will receive a pint glass with the race logo.
The Dead Last Finisher (DLF) in each even will receive a custom award.Age-group medals (3 deep) will be awarded in the following categories, for both males and females:
● 13 and under
● 14 – 19
● 20 – 29
● 30 – 39
● 40 – 49
● 50 – 59
● 60 – 69
● 70 and over
Age-group winner awards from Atlas Wine Co. will be awarded to 21+, for both males and females.
The Fine Print
Event's current local time: 8:27 PM PT
Entry fees to our trail runs are non-refundable in all cases, and we do not offer credits, transfers, or deferrals to future races except as described below. Only registered runners can participate in our races, and you cannot exchange your entry with anyone else in any case.
We are happy to issue a credit worth 50% of your original race fee toward a future Inside Trail Racing event if we receive your cancellation at least 3 weeks prior to the race. Credits will expire 1 year after the date issued. There will be no credit provided if a cancellation is made within 3 weeks of the race.
While we understand that last-minute injuries, conflicts, emergencies, deaths, and other unfortunate events affecting registered runners can happen and may impact your plans for participation, we must adhere to our cancellation policy stated above and cannot offer any credits, refunds, transfers, or deferrals in any of these cases.
If the situation does arise where ITR must outright cancel an event for any reason, there will be no refunds. This could include earthquakes, floods, extreme weather, unsafe air quality, pandemics, or any other “Act of God”. ITR at its sole discretion may choose to offer future race credit or deferrals in these force majeure situations, depending on the circumstances and how close to the race date the event was cancelled. We will communicate with all registered runners as soon as possible regarding the cancellation and any pertinent information.
We do not cancel races due to rain or heat. Due to trail work, closures, or for myriad other reasons, permitting agencies may require changes to the publicized courses at any time prior to an event. This is out of our control, and we therefore will not offer refunds, credits, deferrals, or transfers (except as described below) in such a situation. If a race location is changed, but still hosted on the same day, we will automatically transfer the registration over to the new venue, or entrants may choose to run the race remotely and we will mail awards. If a race is postponed all entrants will be transferred to the new date.