Chicago 11 Hour Endurance Run
Willow Springs, United States • 16 May 2026
Event overview
The Chicago Yeti 7/11 Hour Endurance Run is scheduled for May 16, 2026 at Wolf Road Woods in the Palos Preserves, Willow Springs, IL (9800 Wolf Rd). The event offers two timed formats: a 7-hour endurance run and an 11-hour endurance run. The course is a loop of 4 miles, and awards are given in each category. Race timing and live lap counting are provided by a professional timing company.
Course, aid and policies
The loop combines single-track and double-track trails, rolling hills, and some runnable sections, with viewpoints including ponds and a historic reactor site. Trail markings are provided. The Yeti 7/11 aid station provides a range of snacks and drinks, and participants may use a personal cooler to accommodate dietary needs. This is a cupless event; runners must bring a reusable cup (foam or collapsible for hot liquids and a reusable cup for other drinks).
The event has inclusion policies that accept entrants’ declared gender. Athletes with disabilities may use tethers for visual impairment and may use leg prosthetics; crutches, braces, or poles are allowed with race director approval. The course is not suitable for wheelchairs. The organizer states that entries are nonrefundable and transfers or deferrals are not offered. Visit the organization's website for the most recent information.