MSO11639 - Treborough Quarries (Monument)


The quarry produced Treborough slate and was owned by the Trevelyans of Nettlecombe Court. It is recorded as providing 2000 slate tiles for Dunster Castle in 1426. It ceased production in 1938; the original quarry became a rubbish dump.

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Type and Period (4)

Protected Status

  • None recorded

Full Description

Was an important quarry producing Treborough slate. [1] OS map marks tunnel under road to waste tips. [4] The 1st Edition Ordnance Survey map marks the tunnel route and also shows a smithy on the site. [5] 'Tramway' also marked on old Ordnance Survey map. [6] This is recorded as a source of material for construction in Somerset and Exmoor by English Heritage. Stone was extracted for around 500 years, not closing fully until 1938. Ilfracombe Slates were extracted at this site, which were quite waved in surface, but sufficient for roofing, doorsteps, cisterns and flooring. Also extracted was sandstone, which was used in local building. The quarry provided slate for Dunster Castle in 1426. [7] The last slate quarries in Devon ceased trading in the early 20th century and Treborough quarry in Somerset closed in 1938. In the Ilfracombe Slates Formation (Middle Devonian) the quarries at Treborough (Treborough slates) were a well known source. Howe commented on their quality in 1910; "‘... the Devonian strata in north Devon and Somerset have afforded rough slates strong and sound, but with a rather wavey cleavage surface, and not capable of being split at all thin. They have been worked in a small way about Countisbury and Treborough, in the Bredon Hills. As a rule these slaty rocks are too much crinkled and folded to make good slate." [8] In 1975 the site was being used as a rubbish dump by the local councils. The slates at Treborough are exceptional in the area as it is the only source of high quality slate, and provided slates for the roofs on the Brendons. In the 1790s the quarry belonged to the Luttrells, with the site managed by Thomas Reynolds, and did good business, with slate sold to dealers who often received a discount for cash. Gunpowder was used for blasting. [9] An article about the quarry includes a photograph of the interior, showing the cutting shed and stables in c. 1900. The site was owned by the Trevelyans of Nettlecombe Court. An early reference to the site is made in 1426, when 2000 slates were provided to Dunster Castle. The original quarry face was not exhausted until 1863, when a new supply of slate was sought to the west of the main workings. The quarry was abandoned in or just before 1890 but was reopened in 1894, before again closing in 1910. It was once again reopened in 1914 to 1938. The tramlines and wagons went for scrap in World War Two and some of the buildings were pulled down. After the war the spoil heaps and suitable slopes were planted with conifers, although some of the ancient coppiced woodlands remained in 1983. The original deep quarry was used as a rubbish dump for West Somerset but the main working area was preserved as a Conservation Area for both its wildlife and industrial archaeological remains. [10] Walter Raymond described how the quarry appeared towards the end of its use. [11]

Sources/Archives (11)

  • <1> Unassigned: Aston, M. 11.03.76. Somerset County Council.
  • <2> Survey: Western Archaeological Trust. 1980s. Exmoor Aerial Photograph Survey. 0136.
  • <3> Aerial photograph: 1947. LHL CPE/UK/1980. 4326 and 4327.
  • <4> Map: Ordnance Survey Archaeology Division. 1966. 6" sheet ST03NW.
  • <5>XY Map: Ordnance Survey. 1868-1901. County Series; 1st Edition 25 Inch Map. 1:2500. [Mapped feature: #46651 ]
  • <6> Map: Ordnance Survey. c.1904. 1:2500 map, second edition.
  • <7> Monograph: English Heritage. 2011. Strategic Stone Study: A building stone atlas of Somerset & Exmoor. English Heritage. 4.
  • <8> Report: Hughes, T.. 2016. Regional advice note 2: Slating in South-West England. 5,8.
  • <9> Serial: Exmoor Society. 1959-present. Exmoor Review. Volume 16 (1975), Slate-quarrying at Treborough, p24 (RF Youell).
  • <10> Serial: Exmoor Society. 1959-present. Exmoor Review. Volume 24 (1983), "Treborough Slate Quarry and Conservation Area", p22-29.
  • <11> Serial: Exmoor Society. 1959-present. Exmoor Review. Volume 33 (1992), "The disused quarry", p78-80 (W Raymond).



Grid reference Centred ST 0153 3683 (852m by 436m)
Map sheet ST03NW

Finds (0)

Related Monuments/Buildings (1)

Related Events/Activities (1)

External Links (1)

Other Statuses/References

  • Exmoor National Park HER Number (now deleted): MSO8349
  • National Monuments Record reference: ST 03 NW31
  • National Park: Exmoor National Park
  • Pastscape HOBID (was Monarch UID): 975134
  • Somerset SMR PRN: 34140

Record last edited

Aug 17 2020 2:49PM


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