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⏵ Course guide · California ultra

Quad Dipsea Course Guide

The Quad Dipsea is a Marin County institution that has run the Saturday after Thanksgiving since 1983, and it is exactly what it sounds like: four crossings of the legendary Dipsea Trail, stairs and all. It is only 28.4 miles, but it stacks about 9,200 feet of climbing into that, so it punches way above its distance. I will walk you through the course first, then give you a pacing and fueling plan that fits all that vert. There are free calculators along the way to dial in your own numbers.

⏵ At a glance

Quad Dipsea quick facts

Date
Saturday after Thanksgiving (Nov 28, 2026)
Location
Old Mill Park, Mill Valley, to Stinson Beach, Marin County, CA
Distance
28.4 mi (four crossings of the Dipsea Trail)
Elevation gain
About 9,200 ft of climb and an equal amount of descent
Start
7:30 AM sharp, Old Mill Park
Cutoffs
Noon at the mile-14 turnaround · 2:15 PM to leave Stinson for lap 4 · 4:30 PM finish (9 hr)
Qualifier
Not a Western States, Hardrock, or UTMB qualifier

These facts come from the official race site and UltraSignup. The race is capped at 250 runners and tends to fill, so check the current date, cutoffs, and entry details before you commit. Race logistics change year to year.

The course: where the Quad Dipsea is won and lost

The Quad is two out-and-back trips along the Dipsea Trail between Old Mill Park in Mill Valley and Stinson Beach, four crossings in all, about 28.4 miles and 9,200 feet of climbing with an equal amount of descent. No shortcuts are allowed, unlike the regular Dipsea and the Double, so you stay on the actual trail the whole way. There is almost no flat to hide on. You are either going up hard or coming down hard for nearly the entire day.

The stairs and the climb to Cardiac

Within a few hundred yards of the gun you are climbing three flights of stairs that rise as tall as a 50-story building, 686 steps in the first three flights alone. They are a shock cold off the start line, and you hit them four times across the day. Past the stairs the trail heads up through an old horse ranch to Windy Gap, then plunges down into Muir Woods across Redwood Creek and starts the long grind up through trees and grassland over sections named Dynamite, the Hogsback, the Rainforest, and finally Cardiac.

The climb to the top of Cardiac is the signature effort of each crossing, and the temptation is to power up it early when the legs feel fresh. Do not. You have got this climb in front of you four times, so hike the steep pitches efficiently and keep your effort honest. The runners who blow up here on lap one or two are walking it by lap four.

Steep Ravine, Insult Hill, and the drop to the beach

From the top of Cardiac the course levels out with big views of the Pacific, then plunges down over the rocks, roots, and stairs of Steep Ravine. This is technical, quad-pounding descending, and doing it eight times total (four out, four back) is what wrecks people. Right after comes Insult Hill, a short, savage little climb that earns its name precisely because it shows up when your legs are screaming downhill. Then the trail eases out across the Moors and rolls the last stretch into Stinson Beach.

Once at Stinson you turn around and run the whole thing back to Old Mill Park. Then you do the full out-and-back a second time for the Quad. Every climb becomes a descent and every descent becomes a climb, which is why pacing the first two crossings is the entire game.

Aid, drop bags, and the cutoffs

Aid is limited and the spacing is real: the official stations sit at the start, Cardiac (about 4.3 miles into each crossing), Stinson Beach (about 7 miles), and the mile-14 turnaround back at Old Mill Park. Drop bags are only allowed at that mile-14 turnaround, so plan to restock there and carry what you need across the stair climbs and the Steep Ravine sections in between.

The cutoffs are spread across the day so you cannot bank everything for the end. You have to be back through the mile-14 turnaround by noon (4 hours 30 minutes), out of Stinson onto your final crossing by 2:15 PM, and across the finish by 4:30 PM for a 9-hour limit. For the distance that is forgiving, but the terrain eats time, so know your splits going in.

Pacing strategy for a vert-stacked out-and-back

With 9,200 feet of gain crammed into 28.4 miles, the Quad is about managing effort across four identical crossings, not chasing a pace chart. The course is symmetrical, so your lap-one effort tells you exactly how the day is going to feel three more times. Run it by feel on the climbs, not by your flat-ground splits.

Pace the climbs by grade, not by the watch

Your road pace is meaningless on the Dipsea stairs and the Cardiac grind. What matters is grade-adjusted effort, so hold an output you can repeat four times and hike the steep pitches without feeling bad about it. The classic Quad mistake is bombing the early descents and powering the first climb because it feels easy, then having nothing left for crossings three and four. Use a grade-adjusted pace to turn your real fitness into honest climbing and descending targets, and you will not torch the first half.

Build a vert-aware finish prediction

Do not guess your Quad finish off a road time, and do not even trust a flat 50K time here. The 9,200 feet of climbing, the matching descent, the stairs, and the technical footing all add real time. A vert-aware finish prediction that accounts for this much climbing per mile gives you a realistic window and lets you work backward into the noon and 2:15 cutoffs, so you know how much buffer you actually carry through each crossing instead of guessing.

⏵ Free tools to pace this course

  • Grade-adjusted pace calculator to turn your flat fitness into honest targets for the stairs, the Cardiac climb, and the descents you repeat four times.
  • Race-time calculator for a vert-aware finish prediction on this course’s climbing, so you can plan against the noon and 2:15 cutoffs.
  • Race-equivalent calculator to turn a recent race result into a Quad Dipsea goal you can actually hold across four crossings.

Fueling strategy for the duration and the limited aid

Most runners are out on the Quad somewhere around 5 to 9 hours, and the constant hard climbing burns through fuel fast. With aid only at four points and drop bags only at mile 14, carbohydrate, sodium, and fluid carry just as much weight as fitness does.

Carbs: steady and trained

For a 5 to 9 hour effort, aim for around 60 to 90 grams of carbohydrate per hour, and only push the higher end if your gut is trained for it. Hard climbing and hard descending both make it easy to forget to eat, so keep your intake steady and easy to get down rather than gambling on big catch-up doses late. Practice your exact race-day carb rate on long, hilly runs so 80-plus grams an hour feels normal by November, not like an experiment.

Sodium, fluid, and the late-November cold

Marin in late November is usually cool and often damp under the redwoods, so you will not sweat like a summer race, but you can still run low on sodium over a long day, so do not neglect it. The bigger trap is the cold: it blunts your thirst and your appetite, and people quietly under-fuel and under-drink because nothing feels urgent. Keep eating and drinking on a schedule even when you do not feel like it, and carry enough between the limited aid stations to cover the long stair and Steep Ravine stretches.

⏵ Build your fueling plan

Get a carb, sodium, fluid, and caffeine plan per hour built for your weight, your goal time, and the Quad Dipsea’s climbing with the free ultra fueling calculator. Browse the rest of the free running tools at the tools hub.

⏵ Train for it with Summit Line

Get a race-day plan built around YOUR fitness, this exact Quad Dipsea course profile, and your projected splits. Summit Line reads your real training, builds a plan for all that stair and Cardiac climbing, and rehearses your fueling so race day is something you execute, not guess at.

Start free →Explore the demo

Quad Dipsea FAQ

How hard is the Quad Dipsea?

The Quad Dipsea is one of the toughest 28-mile races you can run, way harder than the distance suggests. It packs about 9,200 feet of climbing and the same amount of descent into just 28.4 miles, which is a steeper climb-per-mile ratio than a lot of mountain 100s. You run the legendary Dipsea Trail four times, including those infamous stair flights, with almost no flat to recover on. The 9-hour overall cutoff is generous for the distance, but the relentless up-and-down and the pounding descents are what break people, not the clock.

How much climbing is in the Quad Dipsea?

About 9,200 feet of total climb, and because it is an out-and-back run twice, you descend every one of those feet too. That is roughly 325 feet of gain per mile, which is genuinely steep. The climbing is front-loaded onto short, sharp pitches like the opening stairs, the grind up to Cardiac, and the brutally steep Insult Hill, so you are climbing hard or descending hard almost the entire day with very little runnable flat.

What are the cutoff times for the Quad Dipsea?

There is a noon cutoff at the mile-14 turnaround back at Old Mill Park, which is 4 hours 30 minutes in and marks halfway. You then have to leave Stinson Beach to start your fourth and final crossing by 2:15 PM (6 hours 45 minutes). The overall finish cutoff is 4:30 PM, a 9-hour limit. Confirm the exact times in the current race-day details, since they can shift year to year.

What is the Quad Dipsea course like?

It is two out-and-back trips along the Dipsea Trail between Old Mill Park in Mill Valley and Stinson Beach, four crossings total, with no shortcuts allowed. Within a few hundred yards you hit three flights of stairs (686 steps in the first three flights) climbing as tall as a 50-story building, then it heads through an old ranch to Windy Gap, drops into Muir Woods across Redwood Creek, and grinds up sections named Dynamite, the Hogsback, the Rainforest, and Cardiac. From the top of Cardiac you plunge down the rocks, roots, and stairs of Steep Ravine, hit the short and savage Insult Hill, then roll out across the Moors to the beach. Then you turn around and do it again, twice.

How should I fuel for the Quad Dipsea?

Most runners are out there somewhere around 5 to 9 hours, so treat it like a long mountain effort even though it is under 30 miles. Aim for roughly 60 to 90 grams of carbohydrate per hour, leaning higher only if your gut is trained for it, and keep sodium up to match a cool but humid coastal day. Aid is limited: the official stations are at the start, Cardiac, Stinson Beach, and the mile-14 turnaround, and drop bags are only allowed at mile 14. Carry enough between stops so the all-uphill or all-downhill stretches do not leave you running on empty.

Is the Quad Dipsea a good first ultra?

It is a hard place to start, but it can work if you respect it. The distance is short for an ultra, which is a real advantage, but the constant steep climbing and the leg-destroying descents demand specific prep that a road runner will not have. Train stairs and short steep climbs, train downhill running hard so your quads can take the pounding four times over, and rehearse your fueling. If you put in that work, the 9-hour cutoff gives a prepared first-timer room to finish, but do not show up thinking 28 miles will be easy.

This guide is independent and for planning only. The course details, dates, cutoffs, and aid stations come from public sources and can change year to year, so confirm the current specifics with the official race before you register or run. The fueling and pacing advice is general and not medical advice.