⏵ Course guide · Southern Kettle Moraine, Wisconsin
First run in 1982, the Ice Age Trail 50 is one of the oldest continuously run ultramarathons in the country, sending 50 mile, 50K, and Half Marathon fields through rolling glacial kettle-moraine terrain on the Ice Age National Scenic Trail. I will walk you through the course, then give you a pacing and fueling plan built for eskers, roots, and a 12-hour cutoff, plus free tools to dial in your own numbers.
These facts come from the official iceagetrail50.com race info and about pages. Registration, aid stations, and cutoffs can change year to year, so confirm the current specifics before you commit.
The race starts and finishes at the Nordic Trail head near La Grange, and the 50 mile course changes character once you leave the opening ski trail loop.
The opening 10.68 miles run the Nordic ski trail, a very runnable loop through pines and meadows where sections that were once rocky have been wood-chipped over to protect the ski equipment. It is easy on the feet and joints, a good early stretch to settle in before the terrain shifts.
Past Confusion Corner, the Ice Age Trail proper takes over, delivering rocks and roots on steep climbs and descents as the course scrambles up and over eskers, the glacial ridges the trail is named for. Very runnable stretches through pine forest, meadows, and near wetlands break up the technical sections. Fifty-mile runners are not permitted earbuds outside the Nordic loop, since the trail is shared with horse riders in several places.
Every aid station stocks water, HEED, and soda, plus PBJ sandwiches, meat sticks, potatoes, oranges, bananas, pickles, cookies, chips, and pretzels; gels are available but limited. Fifty-mile drop bags are staged at the Start/Finish, Hwy 12, and Horseriders Camp. The finish area runs a post-race BBQ dinner around 12:15 p.m., catered locally, with craft beer from Central Waters Brewery for registered runners.
The 12-hour cutoff for the 50 mile is fair, not generous, and the terrain shift from fast ski trail to technical, root-strewn singletrack means your early pace should not set your expectations for the whole day.
The opening 10.68-mile Nordic ski trail is genuinely fast and runnable, and it is the right place to move well, not the technical esker terrain later on. A grade-adjusted pace target gives you an honest number for the climbs and rocky descents once the Ice Age Trail proper begins, rather than assuming your Nordic-loop pace holds for the rest of the race.
A vert-aware finish prediction built off your splits through the first section gives you a much more honest read than a flat-course estimate. Given the technical terrain in the back half, check your projected finish against the 12-hour cutoff by the halfway point, not after the terrain has already slowed you down.
⏵ Free tools to pace this course
A 6:00 a.m. start puts you out in cool morning air, and by midday the Kettle Moraine's exposed meadow sections can warm up fast, so plan your fueling and sodium to shift as the day goes on.
Aim for roughly 60 to 90 grams of carbohydrate per hour. Every station stocks the same core spread, so keep your intake consistent rather than skipping stations early and overloading later. Bring your own gels if that is your preferred format, since the race's own supply is limited.
Sodium in the 300 to 700 milligram per liter range covers most runners, leaning toward the higher end through the exposed meadow and prairie sections once the sun is up. Early loops in the cooler morning air can sit lower; adjust upward as the day warms.
⏵ Build your fueling plan
Get a carb, sodium, fluid, and caffeine plan per hour built for your weight, your goal time, and an early-May Wisconsin day 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 Kettle Moraine course profile, and your projected splits. Summit Line reads your real training, builds a plan for rolling glacial terrain, and rehearses your fueling so race day is something you execute, not guess at.
Ice Age Trail 50 is one of the oldest continuously run ultramarathons in the country, first held in 1982, and it has historically served as a Western States 100 qualifier. The course runs rolling glacial kettle-moraine singletrack and cross-country ski trail through the Southern Kettle Moraine State Forest, with no single defining climb but a steady diet of rocks, roots, and terrain changes. The 50 mile carries a 12-hour cutoff from a 6:00 a.m. start, and the field is genuinely competitive year to year, which tells you this is not a soft old-school course, just a well-earned classic one.
The race does not publish a single total elevation-gain figure for the 50 mile. What the course offers instead is constantly changing terrain: the opening Nordic ski trail section is a very runnable 10.68 miles through pines and meadows, much of it wood-chipped over rocky ground to protect the ski trail equipment. From there, the Ice Age Trail proper delivers real changes in elevation and grade, with rocks and roots on steep climbs and descents as the course scrambles up and over eskers, the glacial ridges that give the Kettle Moraine its name.
Early May in southern Wisconsin can run cool in the morning and warm up through the afternoon. Aim for roughly 60 to 90 grams of carbohydrate per hour, and sodium in the 300 to 700 milligram per liter range. Every Ice Age aid station stocks water, HEED, and soda (Coke, Mountain Dew, Ginger Ale), plus PBJ sandwiches, meat sticks, potatoes, oranges, bananas, pickles, cookies, chips, pretzels, and candies. Gels are available but limited, so bring your own if you rely on them. For the 50 mile, drop bags are staged at the Start/Finish, Hwy 12, and Horseriders Camp. Build your numbers with the free ultra fueling calculator before race day.
The 50 mile and 50K both close at 6:00 p.m. sharp: a 12-hour cutoff for the 50 mile from its 6:00 a.m. start, and 9 hours 45 minutes for the 50K from its 8:15 a.m. start. The Half Marathon closes four hours after its 9:00 a.m. start, at 1:00 p.m. Results are scored by gun time, and no one crossing the 50 mile finish after the 12-hour cutoff is officially recorded. There are also several hard intermediate cutoffs at aid stations along the course; runners who miss them are asked to turn in their bibs.
The course opens on the Nordic ski trail, a very runnable 10.68-mile loop through pines and meadows with wood-chipped tread in the rockier sections. From Confusion Corner onward, the Ice Age Trail proper takes over, with real changes in elevation, grade, and vegetation: rocks and roots on steep climbs and descents as the trail scrambles up and over eskers, alternating with very runnable stretches through pine forest, meadows, and by wetlands. Fifty-mile runners are not permitted earbuds or headphones outside the Nordic loop, since the trail is shared with horse riders in several sections.
It can be, if you respect the cutoff. This is one of the oldest continuously run ultras in the country, which means a well-worn course, an experienced volunteer base, and a genuinely fun post-race BBQ and craft beer scene at the finish. The 12-hour cutoff for the 50 mile is fair but not generous, so a well-prepared first-timer who has trained on rolling, technical singletrack and respects the eskers rather than trying to run every one of them has real room to finish and enjoy the old-school atmosphere this race is known for.
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<a href="https://runsummitline.com/guides/ice-age-trail-50">The Ice Age Trail 50 course guide</a><iframe src="https://runsummitline.com/embed/race/ice-age-trail-50" style="width:100%;max-width:420px;height:180px;border:0;" loading="lazy" title="Ice Age Trail 50 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.