The Kettle Moraine 100 Race Guide
The Kettle Moraine 100 is a storied ultramarathon that weaves its way through the rugged beauty of southeastern Wisconsin’s Kettle Moraine State Forest. Runners embark on an epic 100-mile journey that has tested endurance athletes since its inception in 1996. The event serves as a Western States 100 qualifier and is a key fixture in the Midwest Grand Slam of Ultrarunning. With its mix of rolling terrain, dense woods, and open prairies, this race demands careful preparation and mental grit from start to finish.
When It Is Run
The 100-mile event is held annually on the second Saturday of June, placing the 2025 edition on June 14th. Dawn breaks early in mid-June, offering long daylight hours for runners to tackle the first section before the sun sets. Packet pick-up takes place Friday afternoon at the Nordic Trailhead, ensuring participants have time to familiarize themselves with race logistics. While the race begins in the cool morning air, the journey extends well into the night, giving runners a unique experience of both daylight and nighttime trail running.
How to Qualify or Register
Registration for the Kettle Moraine 100 opens at 11 am Central on January 1st via UltraSignup. The race sells out rapidly, and a waitlist is maintained for runners who wish to secure a last-minute spot. Entrants into the 100-mile must complete eight hours of community volunteer work, such as trail maintenance or race support, to satisfy the race’s volunteer requirement. Those seeking a Western States 100 qualification must finish within the 30-hour cutoff. Early rollover credits are available for runners who withdraw by set deadlines, ensuring a pathway to future editions without re-entering the full lottery.
Particular Challenges
Despite its moderate elevations, the Kettle Moraine course presents a relentless sequence of short climbs and descents that can sap strength over the course of 100 miles. The Ice Age National Scenic Trail backbone features a roller coaster of hills that, though never overwhelmingly steep, exact a high cumulative toll on quads and calves. Trail surfaces vary from pine-needle-soft woodland paths to rocky, root-strewn sections that require constant attention to foot placement. Open prairie and marsh areas offer brief respites, but exposure to midday sun and wind can affect pace and fluid needs. The long night section brings additional challenges of navigation, maintaining morale, and managing sleep-deprivation fatigue.
Course Format
The full distance consists of two out-and-back segments. The first leg covers roughly 62.9 miles outbound before turning, and the second leg retraces a 37.3-mile section back toward the start area. This design allows runners to pass aid stations twice, offering crucial support and mental milestones as athletes loop through familiar terrain. Breaks at the turnaround points enable crews to meet participants with fresh supplies and pacers before the final push. Although repetitive, the format gives runners a psychological boost when they recognize familiar landmarks on their return.
Elevation Profile
Runners face approximately 8,801 feet of cumulative ascent and the same amount of descent over the course. The trail undulates between a low point of about 840 feet at the start and a high point near 1,070 feet, framing a landscape of gentle ridges and valleys. No single climb dominates, but the repeated five-to-ten-percent grades over rolling hills create a taxing “roller coaster” effect. Elevation gains are spread throughout the course, preventing long flat sections and contributing to the race’s reputation for constant, grind-style effort.
Terrain Breakdown
Nearly the entire 100-mile loop is run on natural trails, with paved road crossings comprising only a couple hundred feet. Approximately 80 percent of the course snakes through wooded sections blanketed in pine needles, while the remaining 20 percent traverses open prairie or marshland. Runners encounter a mix of hard-packed dirt, loose rocks, exposed tree roots, and occasional muddy patches after rain. The soft forest floor provides welcome relief, but technical sections demand careful attention to prevent slips and falls.
Time Limit & Cutoffs
Participants must complete the course within 30 hours to earn a finish. In addition to the overall cutoff, there are intermediate deadlines at key aid stations. For the 100 km distance—an option for those dropping at mile 62.9—runners must pass the Horseriders aid station by 10:30 pm on race day to remain in the event. Other staffed aid stations impose similar time checks to ensure runner safety and logistical viability, though exact cutoff times vary slightly year to year. Those missing checkpoints are politely asked to withdraw or switch to a shorter distance to maintain the race schedule.
Aid Stations
The Kettle Moraine 100 features a well-planned network of 21 staffed aid stations and 8 unstaffed water stops spread across the entire course. These stations are positioned at intervals ranging from 1.9 to 9.1 miles apart, ensuring runners never face overwhelming distances between sources of support. Drop bags can be placed at select crew-accessible aid stations, including Emma Carlin, Bluff Road, Nordic, Highway 12, and Rice Lake. The logistics team moves all drop bags from the Nordic start area at 7 am on race day, transporting them to their designated stations and returning them when each aid station closes. Crews have access to only certain aid stations, with strict rules prohibiting support at locations like Natalie’s Station, Wilton Road, and Highway 67.
Mandatory Gear
While Kettle Moraine 100 does not publish a specific mandatory gear list comparable to events like UTMB, runners are expected to carry essential safety and navigation equipment throughout the race. The course rules emphasize that participants must carry adequate hydration at all times, as distances between aid stations can reach up to 9.1 miles. Runners are strongly advised to carry a pack with water bottles, a flashlight for nighttime running, appropriate clothing layers for weather changes, and basic nutrition supplies. The race provides timing chips that must be worn at all times, along with race numbers displayed visibly on the front of the body. Given Wisconsin’s variable June weather conditions, participants should prepare for temperatures ranging from cool pre-dawn starts to potentially hot and humid midday conditions.
Crew & Pacing
Pacing is allowed starting after 6:30 pm or after the 100-kilometer mark, whichever comes first for individual runners. Pacers can only join participants at crew-accessible aid stations, which include Emma Carlin, Bluff Road, Nordic, Highway 12, and Rice Lake. Crews are strictly prohibited from providing assistance at non-crew aid stations, and violations of this rule result in immediate disqualification. The race allows some flexibility for runners over 60 years of age, who can pick up pacers at Highway 67 during their second pass at mile 37. Vehicle access is generally good at crew-accessible stations, with most located near roads for easy parking, though some locations like Highway 67 have limited parking that requires all four tires to be completely off the roadway.
Navigation
The Ice Age Trail provides the backbone for approximately 65 miles of the course, creating a well-established path through most sections. Race organizers take great pride in thorough course marking, with Course Director Sid Wegener personally overseeing the marking process on Wednesday and Thursday before the event. GPS files in .gpx format are available for download from race resources, allowing runners to load the course onto compatible devices like Garmin watches. The course features a mix of clear trail sections and some technical areas where careful attention to markings becomes crucial, especially during nighttime hours. Runners who get off course must backtrack to where they made the wrong turn and continue from the correct location, as cutting the course results in immediate disqualification.
Finish Rates
Historical completion rates at Kettle Moraine 100 vary significantly based on weather conditions and yearly factors, with some years experiencing challenging finish rates. The 2021 100-kilometer race saw a notable 50 percent DNF rate due to extreme heat and humidity conditions. For the 2025 100-mile race, 137 runners successfully crossed the finish line to earn their coveted Kettle Moraine buckles. The 2025 100-kilometer event recorded 78 finishers out of the total field. Weather plays a particularly significant role in completion rates, as the early June timing can bring hot, humid conditions that challenge even experienced ultrarunners. The course’s rolling terrain and cumulative elevation gain of 8,801 feet also contribute to the physical demands that affect finishing percentages.
Special Features
Finishers of the 100-mile distance receive the signature Kettle Moraine belt buckle, with sub-24-hour finishers earning a larger, more prestigious version. The buckle design tells the story of the race through artistic elements, featuring copper coloring to represent classic kettles, topographical elevation patterns from actual Kettle maps, pine tree representations, and owl eyes symbolizing the determination needed to run through day and night. The race serves as a Western States 100 qualifier and holds a place in the prestigious Midwest Grand Slam of Ultrarunning. Prize money was introduced in 2025, with $250 awarded to both the male and female overall winners, plus an additional $250 for any new course records. The 2025 race witnessed Reese Slobodianuk setting a new men’s course record of 14:15:22, nearly an hour faster than the previous mark that had stood since 2009.
Previous Winners
Recent course record holders demonstrate the exceptional caliber of competition at Kettle Moraine. Reese Slobodianuk claimed the 2025 men’s 100-mile title in a record-breaking 14:15:22, while Emily Muhs won the women’s division in 19:43:54. The current women’s course record belongs to Michelle Magagna, who ran 16:58:18 in 2022. Historical records show Donna Perkins holding the longstanding women’s mark of 18:12:30 from 1998, while Zach Gingerich’s previous men’s record of 15:17:32 from 2009 stood for over a decade before Slobodianuk’s breakthrough performance. In the 100-kilometer division, Michael Borst holds the men’s record of 8:34:58 from 2015, and Kami Semick owns the women’s mark of 9:45:13 set in 2005.
Official Contact Info
Race Director Michele Hartwig serves as the primary point of contact for all race-related questions and can be reached at dirtrunner100@yahoo.com. The main race communication also flows through Kettle100Run@yahoo.com for general inquiries and race information. Course Director Sid Wegener oversees all aspects of trail marking and course management, working closely with the volunteer coordination team. For specific volunteer opportunities related to course marking, participants can contact volunteer coordinator Michelle Curcio at jnmcurcio@yahoo.com. The race maintains active communication through social media platforms including Facebook, Instagram, and Twitter, as well as through the official website at KettleMoraine100.com for updates on training runs and special events leading up to race weekend.