Drift

A near-horizontal underground passage driven into a hillside or seam outcrop — used either as a mine's main means of entry, cutting straight into a lode or seam without the expense of a shaft, or as a general-purpose haulage, ventilation or connecting tunnel within a mine already reached some other way. Not to be confused with 'glacial drift', the unrelated geological term for loose surface sediment deposited by ice.

Historical usage

Among the earliest forms of mine access in Britain, since a seam or vein outcropping on a hillside could be driven into directly, with no need to sink and equip a shaft first. Remained the standard entry method wherever the terrain allowed throughout the coal, metal and industrial-mineral industries — common across the steep valleys of the South Wales coalfield, in Staffordshire gypsum mining, and in the coastal jet workings of the North York Moors.

How it worked

A drift was driven horizontally, or at a shallow gradient, directly into a hillside from an outcrop, following the seam or vein where it served as a mine's primary access route, or cut through barren rock where it served purely as a haulage or ventilation connection between workings already reached another way. Unlike a shaft, a drift needed no winding engine to raise material to the surface — coal, ore or stone could be hauled straight out along a level or gently graded passage.

Why it was used

Driving a drift was cheaper and quicker than sinking a shaft, and, wherever a seam or lode actually outcropped on suitable ground, avoided the substantial capital cost of permanent winding machinery altogether.

Risks & limitations

A drift could only be used where the local topography — a hillside, a valley side, a seam genuinely reaching the surface — actually allowed a horizontal or shallow-graded route in; flatter-lying or deeper deposits still needed a shaft regardless of how many drifts served the shallower ground nearby.

Regional variation

Used across British coalfields and metal-mining districts alike; distinct from a Level, which specifically follows a lode, and from an Adit, which is specifically driven to drain a mine — a drift can serve either purpose, or simply general access and haulage, without either of those more specific implications.

Images

Mines associated with this term

Included only where MineArchive's own research gives a reasonable evidential basis — not every mine where this might plausibly apply.

• Big Pit — Torfaen (well documented example)
  The mine's own recorded history explicitly describes the pit being converted to drift working in 1973.
• Fauld — Staffordshire (well documented example)
  The mine's own recorded summary, history and workings explicitly describe horizontal gypsum drift mining and drift workings.
• Glendinning (Louisa) Mine — Dumfries and Galloway (well documented example)
  The mine's own recorded workings explicitly describe the Middle Drift level.
• Grove Rake Mine — County Durham (well documented example)
  The mine's own recorded history and workings explicitly describe Rake Level as a horizontal drift.
• Hook Colliery — Pembrokeshire (well documented example)
  The mine's own recorded history, workings and closure notes explicitly describe the West Drift and its flooding.
• Strontian Mines — Highland (well documented example)
  The mine's own recorded history explicitly describes drift working of a barytes deposit from 1982.
• Tower Colliery — Rhondda Cynon Taf (well documented example)
  The mine's own recorded history explicitly describes the first Tower drift mine, sunk in 1864.
• Whitby Jet Workings — North Yorkshire (well documented example)
  The mine's own recorded summary, workings and current condition explicitly describe inland drift mines and drift entrances.

Disasters associated with this term

Included only where MineArchive's own research gives a reasonable evidential basis, with the nature of the relationship stated — not every disaster where this term might plausibly apply.

• Hartley Colliery disaster, 1862 (contextual relationship)
  The disaster's own recorded rescue account explicitly describes rescuers breaking through to the furnace drift.

Sources

1. (secondary) Drift mining — Wikipedia
2. (secondary) Drift | mining — Encyclopaedia Britannica

Record created: 24 August 2026 · Last researched: 24 August 2026