In the middle of winter, with 17 hours of darkness, 500 competitors head north of Inverness for one of the world's toughest mountain bike races - the Strathpuffer 24-hour marathon.
Have a watch here
Also have a look at the other episodes in the series its a great show and we dont have one like it in England.
Also somewhere on it is Joe from NAV4. See if you can spot him? Jules Fincham from Cyclewildscotland is also there at about 30mins in