The Next Loop 40M/50M Challenge | Half Day Forest Preserve
About this race
The 40/50 Mile Challenge
The 40/50 Mile Challenge is a continuous loop endurance race designed for runners who want to push beyond traditional race formats while benefiting from a fully supported, centralized course.
Held alongside The Next Loop Endurance Series, this event runs on the same 3.1-mile (5K) loop, but unlike the hourly format, competitors in the 40/50 Mile Challenge run continuously with a strict time cutoff.
This format offers a true ultra-distance experience—simplified logistics, consistent footing, and constant access to aid and support.
Event Format
Distances: 40 Miles or 50 Miles
Loop Length: 3.1 miles (5K)
Course Type: Continuous loop trail race
Time Limit: 12 hours
Start/Finish: Same location each loop
Aid Station: Fully stocked at every lap
Staging Area: Designated personal staging area near start/finish
Runners complete repeated loops until they reach their chosen distance or the time limit expires.
Who Should Run the 40/50 Mile Challenge
This event is ideal for:
Runners attempting their first ultra distance
Athletes stepping up from a marathon or 50K
Experienced ultrarunners seeking a fast, efficient course
Competitors who value logistics simplicity and strong support
The loop format removes navigation concerns and allows athletes to focus entirely on pacing, fueling, and mental toughness.
Pick your distance
Trail running
40M, 50M
Typical race-day weather
Based on 1 year of Open-Meteo archive data for this event's race dates in Vernon Hills, plus the 3 days either side.
The sun rises at 6:14 AM and sets at 7:31 PM local time (CDT) in Vernon Hills on August 29, 2026 — 13h 16m of daylight.
Course
No course map published yet.
The organizer hasn't released a route for this event, and we don't publish guesses. If you're the organizer, send us a GPX file and we'll draw the profile.
Reviews
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Other races near Vernon Hills
Different organizers, within 40 miles, in the next three months
Long Grove's Prairie State Half Marathon, 10K & Oktoberfest 5K
Riverside Foundation Halloween Hustle 5K Walk or Run
Long Grove Turkey Trot 5K & 8K
Race to Zero
Where this page comes from. Race details were last updated on . We re-check listings regularly and again in the week before race day.
- Entries, prices, waves and inclusions — the event's official registration page
- Temperature and humidity — Copernicus ERA5 reanalysis via Open-Meteo (CC BY 4.0)
- Elevation and terrain relief — Copernicus DEM GLO-90, ESA (CC BY 4.0)
- Comparisons and counts — Race Discovery calendar, 3 Vernon Hills events
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