Braich yr Oen Mine

Overview

A small copper mine on the slopes of Cwm Llan below Snowdon, worked from 1825 into the 1880s, usually together with the Hafod y Llan copper mine below it.

History

Braich yr Oen is a copper mine in Cwm Llan, on Snowdon's southern slopes, just below the site of the modern hydro-electric dam and above the old Hafod y Llan copper works. It was worked from about 1825 into the 1880s, generally together with the Hafod y Llan mine, whose ore was sold at Swansea from 1825. The mine had its own transport link to the Hafod y Llan slate quarry higher up the cwm.

Like the other Cwm Llan workings, it was worked in conditions harsh enough that dams burst in storms and, by one report, a blacksmith's anvil was blown away in a gale. Its levels climb the hillside above the valley floor; one adit has kept part of its bridge-rail tramway, and ruined mine buildings stand by its spoil tips.

Geology

Unknown.

Workings

Levels driven into the hillside above Cwm Llan, one adit with a bridge-rail tramway partly in place.

Closure

Worked into the 1880s.

What remains

Ruined, roofless stone buildings stand beside the spoil tips; one adit kept part of its tramway.

Ruined mine buildings, spoil tips, and level entrances on the hillside.

Redevelopment

National Trust land on the Hafod y Llan farm, within Eryri National Park; a hydro-electric dam stands just above.

Related mines

• Hafod y Llan Copper Mine — Neighbouring Cwm Llan copper mines, often worked together.
• Hafod y Llan Slate Quarry — Linked by its own transport to the Hafod y Llan slate quarry.

Recorded claims

Individual factual claims, each attached to the source(s) that support it below. Where sources disagree, both are kept.

• Braich yr Oen was worked from 1825 into the 1880s, often together with Hafod y Llan. ¹
• Braich yr Oen copper mine, just below the modern hydro dam, was connected to the Hafod y Llan quarry by its own transport system. ²
• Levels of the Braich yr Oen copper mine lie further up the hillside, one adit having a bridge-rail tramline partly intact. ³
• Braich yr Oen is a disused copper mine in the Cwm Llan area near Bwlch Cwmllan. ⁴

Sources

1. (secondary) Braich yr Oen (Buddlepit Mine Database) — Buddlepit Mine Database
2. (secondary) Stunning Eryri valley with tunnels, pits and rope swings across unbelievably beautiful pools — Daily Post (North Wales Live)
3. (secondary) Llanberis, Snowdon and Nant Gwynant (Section 21) — Jaggers Heritage
4. (secondary) Braich yr oen — Festipedia (FR Heritage Group)

Record created: 19 October 2026 · Last researched: 19 October 2026