The Tough Mudder is an obstacle course race. First held locally in 2013 at Gunstock, the event moved to the NH Motor Speedway in 2016, then back to Gunstock in 2018 before the local version was discontinued. The event continues to be held at roughly two dozen locations elsewhere in the USA.

Billed as the “toughest event on the planet”, the “Full Mudder” is a 10 mile, 20 obstacle course race, originally designed by British Special Forces. For the less tough, there’s a “Half Mudder” (5 miles, 13 obstacles); and a 10 mile “Tougher Mudder” competitive race. Full Mudder participants brave freezing cold water, wade through thick mud, tackle underwater tunnels, finesse high ropes, scramble through multiple cargo nets, and navigate their way through a gauntlet of electrified wires. The course is a test of all-around strength, stamina, and mental grit, but also a test of camaraderie and team effort, as participants need to help each other to make it though the course. Participants may don traditional running attire, but costumes are encouraged.