About This Event

Get ready for an extraordinary challenge as the Tunnel Marathon gears up for its second spectacular outing on Saturday 21 November 2026. This year's event will once again be hosted at the Ucap Bunker in Portsmouth, promising an experience unlike any other for endurance athletes. Runners will have the unique opportunity to take part in what is recognised as the UK's inaugural fully underground marathon, delving into a truly distinctive subterranean setting. The course, laid out within the atmospheric confines of the bunker, is designed to test the mettle of even the most seasoned competitors, offering a formidable yet unforgettable race. For those eager to secure their spot on the start line and discover more about the entry process and associated costs, all the necessary information is readily accessible via the official event website. Prepare yourself for an underground adventure that will push your limits.

Frequently asked questions

Staying overnight?

Hotels within walking distance of Ucap Bunker.