Nearly 700 people had a monster of a day at Loch Ness as they faced an endurance test which got harder as muscles tired and energy flagged.
Fortunately, the determination of those taking part carried most of the contestants through the Prime Four Beast Race, being held in and around the loch for the first time.
Organiser Richard Lawes, of Fire Trail Events, said: “There were 30 obstacles over a distance of more than six miles, half of which were natural, such as bogs and swamps, and the other half constructed.
“Many people struggled with three towers of bale, each 20ft high, which people had to climb, and the slide into Loch Ness, after which they had to swim for about 50ft.”
The average finishing time was 90 minutes, which makes the achievement of winner Carl Fisher, who romped home in 49 minutes, all the more remarkable.
Mark MacGruer, 44, from Inverness, said: “It was a good day. There was a team of three of us taking part, but we never treated it as a race, more a bit of fun where we helped each other along the way, which made it more enjoyable.
“The highlights were the various obstacles in the water, when you had to go under, as well as avoiding giant rods, climbing through small tunnels, and sliding into the loch for a dip.
“It was very well run, considering that it was the first time it had been held at Loch Ness, and hopefully it will become an annual event.”
Joining distillery worker Mr MacGruer at Saturday’s event were Derek Brindle and Steven McIntosh.