Skip to main content

Shaping the Landscape: Threepwood Quarry

Stoop and room workings to extract high quality sandstone

Known locally as Sandyholm Caves, Threepwood Quarry was worked for its high quality sandstone. Along with several quarries to the north, the quarry is said to have supplied stone for the construction of the now demolished Hamilton Palace.

The entrance to Threepwood Quarry, mined for the high quality 'Passage Formation' sandstone

Initial workings on the surface of the sandstone were extended underground in a relatively extensive network. These were called ‘stoop and room’ workings which is a system of mining by a network of galleries, which are supported by pillars or stoops, which are a broad pillar of coal, or any other mineral, left in as support.

The sandstone is known as ‘Passage Formation’ and can be seen between Dalserf and Threepwood. The sandstone here is part of a belt of sandstone that runs throughout Central Scotland, created during the mid to late Carboniferous period (330 – 300 million years ago). This period was somewhat drier than the earlier Carboniferous period (360 -310 million years ago) which was characterised by river delta, and swampy, tropical forests, and left behind older limestone bearing rocks.

Stoop and room workings in sandstone, Threepwood Quarry

The geological sites and features of the Clyde and Avon Valley tell a dramatic story of the development of the landscape over 400 million years, from ancient sandy streams, river deltas, swampy forests and glaciers. The rocks and rivers of this story shaped the heritage, and remain a source of power, havens for woodland and wildlife, and places of recreation and creative inspiration today.

Inside the stoop and room workings at Threepwood Quarry

Travel through time to reveal the hidden history in the rocks and landforms by exploring the other ‘Shaping the Landscape’ museum items below, and visiting the Shaping the Landscape Exhibition at New Lanark. Read the full report by clicking on the ‘Shaping our Landscape Trail Report’ link under ‘Find Out More’, or below. Whilst many ‘Shaping the Landscape’ sites are accessible to walkers, some sites are inaccessible, but featured as museum pieces to help demonstrate the development of the Clyde and Avon Valley.


Area Guide