Iron men and women – A 3.8 kilometer open-water swim, followed by a grueling 180 kilometer bike ride, rounded off with a lung-busting marathon. Are you ready to push the limits of human endurance? (All pictures shot by Charlie Crowhurst; courtesy of Getty Images)
Iron men and women – Over the last year British photographer Charlie Crowhurst has covered a number of triathlon events in Europe, producing otherworldly images which highlight the exhausting, lonely reality of endurance sport.
Iron men and women – This photograph by Crowhurst almost has a volcanic feel about it, setting the swimmer against the backdrop of the fiery red sun setting in the distance.
Iron men and women – Each triathlete is given a number before undertaking the challenge. "I guess people do it to give themselves a goal or something to aim for," Crowhurst told CNN. "Perhaps they can't achieve anymore in a working capacity and want to push themselves in another field."
Iron men and women – Crowhurst uses digital filters to create his own unmistakable style. "These events are a real test of not only physical stamina but mental too and I think a lot of people underestimate the mental aspect and how tough that can me," he said.
Iron men and women – One last deep breath before this competitor prepares to take on chilling waters at the Challenge Almere event in the Netherlands.