We've handpicked a selection of unusual, adventurous and down right crazy trail running events for your race calendar consideration. You'll be amazed!
In a sporting world-first, Inov-8 is to stage a downhill running race for 180 nutty competitors on the Streif. The race has been named 'The Descent'.
Here's our round up of 2016's races - perhaps you may find some ideas or inspiration in these for your 2017 trail running adventures?