Got your mandatory kit sorted?
Browse the ultra runners' kit list for all your essential gear.
Slate Trail Ultra - 91 Mile Ultramarathon
If you are looking for an ultra marathon that combines raw mountain ruggedness with a deep sense of history, the Slate Trail Ultra is unmatched. This isn’t just a run around the hills, it is a 91 mile complete circumnavigation of the Snowdonia Slate Trail, taking you deep into the industrial heart of Eryri.
While many races in North Wales focus purely on the summits, this event tells a different story. You will run through a UNESCO World Heritage landscape, tracing the footsteps of the quarrymen who carved these mountains centuries ago. It is a route that feels alive with history, passing through abandoned villages, towering slate heaps, and mist-covered moorlands.
Course
The race begins and ends at Porth Penrhyn, Bangor, the historic port where slate was once shipped to the world. From the coast, you head inland for a colossal 147km (91 mile) loop.
The terrain is incredibly diverse. One moment you are running on well-trodden valley paths, the next you are navigating technical forest trails, crossing wild and boggy moorland, or scrambling up high mountain passes. The route visits iconic areas like Llanberis, Betws-y-Coed, and Ffestiniog, but often via their "back doors", the old tramways and inclines that most tourists never see.
Expect the underfoot conditions to be a proper Welsh mixture: hard-packed slate trails, muddy single-track, and rocky descents that demand concentration, especially when fatigue sets in during the night sections.
With 3,900 metres of vertical gain, this is a significant undertaking. It’s not just the climbing that gets you; it’s the constant change in rhythm. The climbs aren't always the long, steady plods found in the Alps; they can be sharp, punchy, and relentless.
The 36-hour time limit is generous enough to allow for a solid hiking pace on the climbs, but tight enough that you can’t afford to hang around too long at checkpoints.
There is a haunting beauty to this ultra marathon that you don't get elsewhere. Running by headtorch through the skeleton of a ruined slate mill, with the silence of the mountains around you, is an experience that sticks in the memory!
For official entry requirements, mandatory kit lists, and the most up-to-date race rules, please visit the official race website.
