Rat Race Sea to Summit Yr Wyddfa
Forty-seven kilometres from the gates of Caernarfon Castle to the summit of Yr Wyddfa.
47km
29 miles
Nobody has reviewed this one yet
No reviews of the Sea to Summit Yr Wyddfa, and nothing on what people wore. Both are things no organiser publishes and every runner wants before they enter — how it actually went, and what was on your feet.
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The course
What you’re in for
Forty-seven kilometres from the gates of Caernarfon Castle at sea level to the summit of Yr Wyddfa — the highest point in Wales — on a marked course. Late September.
Terrain and trail
Lane, cycle path and lakeside trail out of Caernarfon, then the mountain: a long, stone-pitched climb to the summit with the exposure and weather that go with 1,085m. Marked, but carry mountain kit; the top is a different day from the bottom. A trail shoe with grip.

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Make your race print →Train for it: routes near the start
Routes starting within 20 km of Caernarfon Castle, Gwynedd, nearest first. Each one has a free GPX file and a TRP grade, so you can rehearse the ground before race day.
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How to enter
No date announced for the next running yet. Rat Race’s site ↗ is where it will show up first.

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Common questions
- The Sea to Summit Yr Wyddfa is one distance: 47km (29.2 miles).