⏵ Course guide · Festival loop ultra weekend
Run Woodstock repeats a 16.6-mile loop at Pinckney Recreation Area near Gregory, Michigan, six times for the Hallucination 100 and four for the Happening 100K, both with a 30 hour clock and a festival atmosphere built for camping, music, and community. I will walk you through the loop and event-switching rules first, then give you a pacing and fueling plan built for repeated laps and a long weekend, plus free tools to dial in your own numbers.
These facts come from the official Run Woodstock race details page. Aid station offerings, entry pricing, and intermediate cutoffs can change year to year, so confirm the current specifics on runwoodstock.com before you commit.
Every ultra distance at Run Woodstock runs the same clockwise 16.6-mile loop through Pinckney Recreation Area: 6 loops for the 100 Mile, 4 (with shortcuts) for the 100K, 3 for the 50 Mile, and 2 (with shortcuts) for the 50K.
The loop runs primarily single-track trail, with one stretch of gravel and a few crossings of paved roads that have no traffic control. Your own awareness at those crossings is your responsibility, so stay alert even on tired late-race legs.
100 mile runners who have not completed 4 laps (66.67 miles) within 20 hours get automatically switched to a 100K finish rather than pulled from the course entirely. The same structure applies to the 50 Mile: miss the 9 hour cutoff for 2 laps and you are scored as a 50K finisher instead. It is a genuinely runner-friendly rule that guarantees a real result on an off day.
Woodstock Camp, home to the main Hog Farm aid station, is the hub every runner passes through on every loop. Live music, camping, and a genuine community atmosphere surround the race, and the loop format means you never go too long without seeing familiar faces or your own crew.
The mandatory event-switching cutoffs, 20 hours for 4 laps of the 100 mile, 9 hours for 2 laps of the 50 mile, are not suggestions. Build your pacing plan around them directly.
A grade-adjusted pace target for the 16.6-mile loop tells you an honest per-lap time, but check that number specifically against the 20 hour / 4 lap threshold for the 100 mile before you start. Missing that threshold does not end your race, but it does end your shot at the full 100 mile distance.
The 100 mile requires starting your final loop by 3:00 pm, with additional named cutoffs at Bethel Woods, Food for Love, and Rosemary Forest late in the race. A vert-aware finish prediction, checked against those specific named cutoffs rather than just the overall 30 hour limit, gives you the clearest read on your real margin.
⏵ Free tools to pace this course
A Friday 2:00 pm start and a 30 hour time limit put most 100 mile finishers through a full day, a full night, and well into a second day, in Michigan September conditions that can still run warm.
Aim for roughly 60 to 90 grams of carbohydrate per hour. Because the race is cupless, you need your own bottle or hydration system at every aid station, spaced roughly every 3 to 6 miles on the ultra loop, with hot food available at the Hog Farm and Food for Love stations.
Sodium in the 300 to 700 mg per liter range covers most runners, leaning toward the higher end during the warmer daytime loops, especially early Saturday and Sunday afternoon when September Michigan can still deliver real heat.
⏵ Build your fueling plan
Get a carb, sodium, fluid, and caffeine plan per hour built for your weight, your goal time, and a full September Michigan weekend 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 16.6-mile loop profile, and your projected splits. Summit Line reads your real training, builds a plan for repeated loop racing, and rehearses your fueling so race day is something you execute, not guess at.
The Hallucination 100, the marquee distance at Run Woodstock, repeats a 16.6-mile singletrack loop six times through Pinckney Recreation Area, primarily single-track with a gravel stretch and a few road crossings. A 30 hour time limit gives real margin, but the race enforces mandatory event-switching for runners off pace: if you have not completed 4 laps (66.67 miles) within 20 hours, you get switched to a 100K finish instead of continuing on the 100 mile. That structure means the difficulty here is as much about honest pacing against firm intermediate cutoffs as it is about the terrain itself.
Every ultra distance at Run Woodstock repeats the same 16.6-mile clockwise loop: the 100 Mile does 6 loops, the 100K does 4 loops with shortcuts, the 50 Mile does 3 loops, and the 50K does 2 loops with shortcuts. That means every runner passes through the Hog Farm aid station at Woodstock Camp repeatedly, giving frequent access to drop bags, crew, and the festival atmosphere the race is known for.
With a Friday 2:00 pm start for the 100 mile and a 30 hour time limit, plan for a full day, a full night, and well into a second day. This is a cupless race, so bring your own drinking vessel for every aid station. Aid sits roughly every 3-6 miles on the ultra loop, with hot food available at the Hog Farm (start/finish) and Food for Love (roughly the halfway point of each loop). Aim for roughly 60 to 90 grams of carbohydrate per hour, and sodium in the 300 to 700 mg per liter range, adjusting for September Michigan weather that can still run warm during the day. Build your numbers with the free ultra fueling calculator before race day.
The Hallucination 100 and Happening 100K share a 30 hour time limit from their Friday 2:00 pm start, with named intermediate cutoffs on the final loop: Bethel Woods (mile 90) by 5:04 pm, Food for Love (mile 94) by 6:16 pm, and Rosemary Forest (mile 97) by 7:02 pm. You must also begin your final loop no later than 3:00 pm. The 50 Mile and Freak 50K share a 14 hour time limit from their Saturday 6:00 am start, and 50 milers must complete their first 2 laps within 9 hours to continue toward the full 50 mile. The Mellow Full marathon and Hippie Half get a 10 hour time limit.
Run Woodstock builds mandatory event-switching directly into its rules rather than just pulling you from the course. If you have not completed 4 laps (66.67 miles) of the 100 mile course within 20 hours, you are automatically switched to a 100K finish and scored accordingly, receiving a 100K medal instead of an overall DNF. The same structure applies to the 50 Mile: if you do not complete 2 laps within 9 hours, you are switched to a 50K finish. It is a runner-friendly way to guarantee you leave with a real result even on an off day.
Yes, and the loop format is a big reason why. Because you return to Woodstock Camp every 16.6 miles, crew logistics are simple, drop bags are easy to manage, and the race's own copy notes you will never have to worry about setting out alone thanks to the hundreds of fellow ultra runners sharing the same loop. The mandatory event-switching rule also means a rough day still ends in a real finish rather than a DNF, which takes real pressure off a first-time hundred mile attempt.
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<a href="https://runsummitline.com/guides/run-woodstock">The Run Woodstock course guide</a><iframe src="https://runsummitline.com/embed/race/run-woodstock" style="width:100%;max-width:420px;height:180px;border:0;" loading="lazy" title="Run Woodstock course guide by Summit Line"></iframe>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.