Saturday, Oct 9, 2021 @ 6:30 AM
Registration closes: Thu, Oct 7 @ 10:00 PM

Covid-19 Update

We have received permission from SF Parks and Rec to proceed with our permit application with instructions we will need to deploy additional Covid protocols. More details to follow, but at this point we will be requiring proof of vaccination, mask wearing while in the common areas, safe distancing, minimum touch and a (possible) staggered start as well as limited food and beverage service. Be prepared to be as self-sufficient as you can, especially fluids. Of course, things can change between now and then so stay tuned.

Course Description

WELCOME. Race Headquarters is in the parking lot at the north end of scenic Lake Merced lake at the foot of Sunset Boulevard in San Francisco, California. This is where you will park, check in, get your number, and receive aid.

It's a mostly flat, certified, 4.5-mile loop on either an asphalt path or groomed dirt shoulder around the lake. It's possible to run on the groomed shoulder path about 90% of the loop. There is approximately 100' of elevation gain and loss per loop.

With two exceptions, you will stay on the paved path that circles the lake. There are two spots approximately 0.5 miles after the start of the first lap where you will go straight and not follow the longer paved route. We will try to mark this on race day and will announce it prior to the start.

Runners will enjoy one aid station per loop fully stocked with water, electrolytes, and a wide selection of foods. You will also have access to your vehicle and are allowed to set up supplies near the aid station. A second water fountain is located about half way through the loop.


Runners will be allowed to choose their distance during the race, but a runner can only be a finisher at one distance. Once reaching the 50 km, a runner must decide whether to continue or stop. If the runner stops, he/she is a finisher in that race and his/her tag will be pulled. Choosing to go beyond the 50 km. distance makes the runner an entrant and competitor in the 50 mile event. You cannot continue past one distance and decide later that you want to be scored in the earlier distance. If you have questions, please ask.

There is essentially no cutoff for 50 km. as long as you can keep moving.

50 mile runners have one cutoff to meet based on a 15 min./mi. finishing pace:

They should finish their 10th lap (44.2 miles) by 11 hours, i.e. by 5:30 p.m., into the race.

Start and Finish lines

There are multiple start/stop points along the route. The parking lot at the foot of Sunset Blvd. is "Race Headquarters." This is where you will park, check in, set up your supplies, get aid, and have your completed laps counted. It is also the finish line for the 50k and 50 mile event.

The start line for all races is a 0.52 mile walk from this area, and we will leave about 6:15. Note that it will be dark at this time of the year.

The first running loop for everyone is 3.95 miles followed by multiple 4.47 mile loops.

The first finishing distance is at 50 km. and that is 0.32 miles past Race HQ. We will have timers there to get 50 km. splits for all runners.

The next finishing distance is 50 miles. So that you can finish back at Race HQ, after your 11th full lap you'll run out 0.645 miles to a turn-around point then run back to the finish line at Race HQ. This turn-around point is a little past where we start and will be clearly marked with chalk and a small sign. You'll have 11 laps to get to know this location, but ask us as you go by if you are confused.

Everyone gets a bonafide split at 50 km.

Lighting needs

Civil sunrise is at 6:48 am that day. The start is at 6:30, so you will be running in the dark for part of the first lap. Even though most of the route is on a wide, public path, you might want to carry a small light at the start. You can drop your light near the timing tent.

Civil sunset is at 7:02 pm that day.


If it is your First Ultra please reach out to RD or Mr. Rao's mentor friend RD for a 20% discount code.

All finishers will receive a custom Ruth Anderson Memorial Patch. Age-group awards three deep in ten year increments.

Be prepared to show proof of vaccination at number pick up.

If you think you might set a USATF age-group record, please let us know in advance so we can be sure to have the appropriate timing in place.

For more information on Ruth see

Local time: 10:28 PM


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