The Dormouse Challenge is a six-hour forest running event held at Salcey Forest near Northampton. Runners begin in the morning and have until mid-afternoon to complete as many 5k laps as they wish. This format offers more flexibility than a standard fixed-distance race. A participant might run a single lap, collect a medal and drink, and finish; another could continue until the time limit, completing an ultramarathon distance. Walkers and hikers are also accommodated, so the participants can range from first-timers to those training for long runs or aiming for personal best distances.
The course avoids asphalt, utilizing maintained forest paths composed mainly of crushed stone and well-trodden woodland ground. While dry weather might allow for road shoes, wet conditions can render the narrower paths muddy and challenging, favoring trail shoes. The route features forest trails, areas of bluebells when in season, and a notable hill that adds difficulty to each lap. The event follows a relaxed Big Bear style: aid station provisions may include mince pies, finishers receive a medal and drink, and canicross participants are permitted if dogs are kept on short leads and managed carefully around other runners. Salcey Forest is accessible from the M1 and Northampton, with bus route 33 serving the forest.