Darran Colliery

Also known asDarren Colliery
LocationDeri, Darran valley, Caerphilly — 51.6903, -3.2447 (approximate)
CommodityCoal
TypeCoal
Worked1868–1919
Maximum depthTwo shafts, each reaching the Brithdir seam at 120 yards.
OperatorsRhymney Iron Company (1868–1919)

Overview

A house-coal colliery in the Darran valley near Deri, sunk in 1868 by the Rhymney Iron Company with two shafts to the Brithdir seam at 120 yards. It was reckoned a safe pit and was worked with naked lights throughout its life — until an explosion on a Friday morning in October 1909 killed twenty-seven, five of them rescuers. It closed in 1919.

A memorial at Darran House in Deri to those who lost their lives in the Darran Colliery explosion of 29 October 1909.
Darran Colliery Memorial, Darran House, Deri Julia MacDonald, CC BY-SA 2.0, via Wikimedia Commons

History

The colliery was sunk in 1868 by the Rhymney Iron Company near Deri in the Darran valley, with two shafts reaching the Brithdir house-coal seam at 120 yards. In 1908 it employed 272 men. At about four o'clock on the morning of Friday 29 October 1909, with fifty night-shift men underground, an explosion vented up the upcast shaft and shattered the pit-head casing on which two men were standing, badly injuring both. Twenty-seven died, five of them members of a rescue party (see Disasters, below). Until that morning the mine had been considered safe, and had been worked with naked lights throughout its history. By 1918 only seventy-three men were employed, and the colliery closed the following year.

Geology

The colliery worked the Brithdir seam, one of the house-coal seams of the upper Coal Measures on the eastern side of the South Wales Coalfield, at a shallow 120 yards. House-coal districts of this kind were widely reckoned less gassy than the steam-coal measures below them, which is why naked lights were tolerated here for forty years — an assumption the 1909 explosion destroyed.

Workings

Two shafts, each 120 yards to the Brithdir house-coal seam, with a separate ventilation pit that had a ladder fixed to the side of the shaft. The colliery was connected underground to the neighbouring Gilfach colliery, which is how survivors of the 1909 explosion got out and how the rescue party got in. Naked lights were used throughout the colliery's working life.

Closure

Employment had fallen to seventy-three by 1918 and the colliery closed in 1919.

What remains

The colliery site has been cleared. A memorial at Darran House in Deri commemorates those who died on 29 October 1909, many of them in their attempts to rescue others.

No colliery structures; a colliery memorial at Darran House, Deri.

Nearby mines

Straight-line distance, within 15 km. Show on the map.

Disasters & major incidents

Recorded claims

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

Photographs & further reading

Welsh Coal Mines: Darran Colliery, Deri (reference)

The colliery's sinking by the Rhymney Iron Company, its shafts and seam, and a detailed account of the 1909 explosion — the carpenter who went down the ventilation shaft by ladder, and the rescue party whose oxygen ran out.

View source

Sources

  1. (secondary) Darran Colliery, Deri — Welsh Coal Mines
  2. (secondary) Welsh mining disasters: list of accidents with five or more fatalities — Welsh Coal Mines

Record created: 3 September 2026 · Last researched: 3 September 2026