Backyard Los Montesinos is a last-one-standing endurance race held in Los Montesinos, Spain. It begins at 19:00 from the Pabellón Municipal. Runners do not aim for a fixed finish line; each hour, they must complete a 6.706 km loop and be ready to start again when the hour resets. Failing to meet the cutoff, line up for the next lap, or stopping before the final competitor means elimination.
The start and finish are both at the Pabellón Municipal, centering the event on repeated loops, brief rests, and choices regarding pace, nutrition, recovery, and mental fortitude. The race concludes when a single runner finishes one more loop than all other participants, making it a contest of strategy and mental strength as much as a test of endurance. The sixth edition had 275 participants and included live tracking, hydration, showers, bag drop, a recovery area, race photos, an official shirt, and finisher medals.