Coffin Level

A narrow, hand-dug tunnel with a distinctive coffin-shaped cross-section -- wider at shoulder height, narrowing above and below -- typical of mines worked entirely by hand before gunpowder came into general use.

Historical usage

Coffin levels are found in mines worked before the late 17th century, when gunpowder began to replace hand tools for driving tunnels through hard rock. Some passages are small enough that they must have been dug by children. The technique is documented at Alderley Edge in Cheshire and at mines including Coniston and various Derbyshire lead workings, and largely disappeared once explosives made a full-sized, rectangular tunnel no more costly to drive than a cramped one.

How it worked

Miners cut a groove down each side of the intended passage using hand-held iron picks, then broke out the remaining 'island' of rock left standing in the middle -- removing only as much rock as necessary to let one person pass, shaped to the width needed at shoulder height and narrowing above and below to save further effort.

Why it was used

Driving a tunnel by hand, one pick-blow at a time, was slow and exhausting work -- a single 17th-century tunnel could take three years to complete -- so miners shaped the passage to remove the least possible volume of rock rather than cutting a full rectangular profile they had no need for.

Risks & limitations

Coffin levels are cramped and awkward for anyone but the smallest visitor, and their low, irregular ceilings make them a genuine hazard to explore without care even today.

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.

• Alderley Edge Mines — Cheshire (well documented example)
  Distinctive 18th-century 'coffin levels' -- narrow tunnels with a coffin-shaped cross-section -- survive alongside shafts across the site.

Sources

1. (secondary) Alderley Edge Mines — Wikipedia
2. (secondary) Mining - post-medieval — Derbyshire Caving Club (Alderley Edge Mines survey)

Record created: 31 August 2026 · Last researched: 31 August 2026