Throughout the year, we will be staging 100, 50, and 30-mile races in each of the following National Parks: Peak District, Lake District, Snowdonia and Yorkshire Dales (which one in what season is a secret for now).
This really is a series second to none, running in depths of winter to the running in the searing heat of the sun.
It is as much a personal challenge as a series of races. Pushing yourself to your limits and beyond.
Who's got what it takes to claim the four seasons series medals?