Snowdonia Sea2Sky 25k
Barmouth, Gwynedd
5 Sep 2026
⚠ Start times change frequently. Always check with race organiser or their website for this year's confirmed start time before travelling.
Course map
Map adapted from official race's website
Elevation profile
About this race
The Snowdonia Sea2Sky 25K starts and finishes on Traeth Abermaw beach in Barmouth, on the coast of Eryri (Snowdonia) National Park, covering the second half of the longer 54K route. From sea level, the course heads out over the Barmouth footbridge and joins the Mawddach Trail, taking in stunning views over Bae Ceredigion (Cardigan Bay) and the Llŷn Peninsula as it follows the estuary. The terrain is a genuine mix of coastal viewpoints, forest tracks and rocky trail paths, avoiding the summit of Cadair Idris tackled by the full ultra but still offering a properly hilly, off-road profile. The course is clearly marked with trail flags, tags and signage, with marshals at major junctions and GPX files available for those wanting to follow the route in advance. It's a cup-free event, so runners must bring their own bottle for the aid stations.