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Rat Race Sea to Summit Yr Wyddfa

Caernarfon Castle, GwyneddNo date announced yet

Forty-seven kilometres from the gates of Caernarfon Castle to the summit of Yr Wyddfa.

47km

29 miles

mountainMarked course

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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More from Rat Race

Every Rat Race race →

Other races Rat Race put on, soonest first.

Other races near here

Eryri (Snowdonia) races →

Races from other organisers starting within 30 km of Caernarfon Castle, Gwynedd, nearest first.

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).

Past runnings

2026Sat, 26 Sept 2026