Gnoll Colliery

Overview

The Mackworth family's colliery on the Gnoll estate at Neath: reorganised in 1695 with a tramway from the pits to the town quay, at one time reckoned the foremost coal works in Wales, with a fire engine at work by 1753. It fell almost silent about 1809 and was leased out again in the 1870s.

History

Coal had been got on the Gnoll ground at Neath since at least the fourteenth century, when the accounts of the Manor of Neath returned nothing from coals for want of workmen. The Evans family of the Gnoll held the leases that gave them virtually sole control of coal mining rights at Neath through the seventeenth century, and in 1686 Humphrey Mackworth came into the estate and those interests by his marriage to Sir Herbert Evans's sole heiress. Mackworth made it into something new. In 1695 he reorganised the working of the town pits, improved their ventilation and built a tramway from the pits to the town quay; he set up copper-smelting and silver refining at Neath, raising copper furnaces at Melin Crythan beside the coal pits, and his coal works were reckoned the foremost in Wales of their day, in output and in quality. Waller's account of Sir Carbery Price's mines credits him with a new method of coffering the water out of his shafts and sinking pits, saving the charges of water engines, and with 'sailing wagons' for cheap carriage. A plan of about 1720 marks 'Ginn houses for raising coals', so the winding was still by horse. The pits multiplied under his successors. In 1744 the Mackworth pits were Greenway, New Greenway, Castle, Cole's, Bowen's, Little Greenway and Bassett; by 1751 the Gwainmorgan vein, the Middle and South pits at Cimla, the Gnoll or Mill pit, Tyn-y-wain and Cae-y-pandy had been added. In 1753 a steam - or fire - engine was at work at the Gnoll, among the earliest in Wales. The Mackworth era ended in 1801, and Edward Martin of Morriston was commissioned to report on the condition of the pits to C. Hanbury Leigh, who had married the widow of Sir Robert Mackworth. Martin recommended sinking a new pit beside the Neath canal, pointing out that the price of coal per wey had gone from 42 shillings in 1792 to 61 in 1800, and that with Boulton and Watt's patent on the small rotative engine expiring - an engine that would raise baskets of five hundredweight a hundred fathoms in a minute and a half - the works could save £500 a year. It was not enough. The Gnoll coal operations ceased almost entirely about 1809, and did not restart until the 1870s, when Robert Parsons of Neath and others leased the property and surrendered it four years later, in 1874, to the Hopkinson concern, the Neath Collieries Company. Work went on into the 1920s.

Geology

Worked coal seams of the South Wales coalfield on the Gnoll estate, among them the Little, Hard, Westernmoor, Bodwr, Wenallt, Graigola and Greenway seams.

Workings

Worked from a scatter of pits across the estate rather than one shaft - Greenway, Castle, Cole's, Bowen's, Bassett and others by 1744, with the Gnoll or Mill pit, Cimla's Middle and South pits, Tyn-y-wain and Cae-y-pandy added by 1751. Winding was by horse gin at least until the 1720s, and a fire engine was at work in 1753. Mackworth's tramway of 1695 ran from the pits to the town quay at Neath.

Closure

The main Gnoll collieries were abandoned around the turn of the twentieth century; a small house-coal level worked on into the 1920s under the Graigola Merthyr company before closing.

What remains

The Gnoll estate is now a country park, its grounds laid out with the ornamental ponds and cascades of the Mackworth landscape; the colliery buildings are gone.

Redevelopment

The Gnoll estate is now Gnoll Country Park.

Nearby mines

• Cwrt Herbert Colliery — 2.0 km W
• Eaglesbush Colliery — 2.2 km SW
• Ynys Dafydd Colliery — 2.8 km S
• Dyffryn Main Colliery — 3.0 km NW
• Wern Colliery, Cwmafan — 3.4 km S

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

Recorded claims

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

• The Gnoll collieries were developed by the Mackworth family of Neath; a steam, or fire, engine was at work at the Gnoll by 1753. ¹
• In 1842 a Gnoll Colliery owned by Penrose and Evans worked a twenty-two-inch seam from a single shaft 252 feet deep. ¹
• The Gnoll No. 3 Pit was driven 146 yards to the Westernmoor seam, passing through the Little, Hard, Greenway and Shenkin seams. ¹
• The Gnoll pits abandoned the Graigola, Hard and Little seams in 1886 and the Greenway seam in 1924, a small house-coal level working into the 1920s. ¹
• The workings are recorded among the abandonment plans of the British Geological Survey mine-plans catalogue. ²
• Humphrey Mackworth came into the Gnoll estate and the Neath coal interests in 1686 by marriage to Sir Herbert Evans's sole heiress. In 1695 he reorganised the working of the town pits, improved their ventilation and built a tramway from the pits to the town quay, and his coal works were reckoned the foremost in Wales. ³
• The Mackworth pits in 1744 were Greenway, New Greenway, Castle, Cole's, Bowen's, Little Greenway and Bassett; by 1751 the Gwainmorgan vein, the Middle and South pits at Cimla, the Gnoll or Mill pit, Tyn-y-wain and Cae-y-pandy had been added. In 1753 a steam or fire engine was working at the Gnoll. ³
• A plan drawn about 1720 marks 'Ginn houses for raising coals' at the pits, showing that the winding was then worked by horse. ³
• On the end of the Mackworth era in 1801, Edward Martin of Morriston was commissioned to report on the pits to C. Hanbury Leigh. He recommended sinking a new pit beside the Neath canal, noting that the price of coal per wey had risen from 42 shillings in 1792 to 61 in 1800 and that a Boulton and Watt small rotative engine would save £500 a year. Operations nevertheless ceased almost entirely about 1809. ³
• Work did not restart until the 1870s, when Robert Parsons of Neath and others leased the property, surrendering it four years later in 1874 to the Hopkinson concern, the Neath Collieries Company. ³

Photographs & further reading

Sources

1. (secondary) Westernmoor and Gnoll Collieries (Welsh Coal Mines) — Welsh Coal Mines
2. (primary) Gnoll abandonment plans (BGS mine-plans catalogue) — British Geological Survey
3. (secondary) Coal Mining (Vale of Neath timeline) — The Hopkin Thomas Project

Record created: 23 September 2026 · Last researched: 23 September 2026