Hardy souls pushed themselves to the very limit at Bramham Park in Leeds.
The country estate was staging a British Military Fitness-backed endurance event called the Major Series.
Racers had to tackle an array of punishing obstacles on either a 5km or 10km course.
Participants included Scott Thomson, who tweeted: “Well that’s the @themajorseries smashed for a third time or did it smash me, anyway mission accomplished.”
Another racer, Micky Long, tweeted: “Cracking event, well done to all involved.”
For information about other Major Series events taking place this year, visit the www.britmilfit.com/major-series web page.