Published 3 August 2026 · 7 min read
Bwlch y Groes sits high in the North–Mid Wales uplands and earns its “Hellfire Pass” nickname from gradient and exposure more than from marketing. On a clear day it is sublime. On a wild day it is a place to respect.
The character of the road
Think narrow mountain climbing, steep pitches and views that arrive all at once when cloud lifts. It is a highlight for riders collecting Wales’ high paved roads, and a natural companion piece to other elevated classics such as Gospel Pass.
Conditions that change the ride
Because of altitude, this is among the first routes to feel ice, standing water or dense hill fog. If the valleys are merely grey, the top can be another climate. Check forecasts and be willing to divert.
Riding tips
- Keep entries slow into hairpins — exit views are better when upright
- Expect livestock and the occasional walker near viewpoints
- Use engine braking on long descents to save brakes and nerves
- Photograph from safe pull-ins, never from the carriageway apex
Link north toward Snowdonia highlights like the Llanberis Pass, or read up on Welsh mountain weather before you chase the summit.