Ogof Ffynnon Ddu, also known informally as OFD, is a cave under a hillside in the area surrounding Penwyllt in the Upper Swansea Valley in South Wales. It is the second longest cave in Wales and the deepest in the United Kingdom.
Wikidata Site of Special Scientific Interest, cave, link={{{3}}}
Llwynypia Rhondda Cynon Taff Joint Emergency Centre ⓘ civil defence centre in
Chartist Cave ⓘ cave in Wales
Dan yr Ogof ⓘ Cave system in Wales, United Kingdom
Dan-yr-Ogof ⓘ cave in Wales
Grotto in Gnoll Estate ⓘ Grade II listed building in Neath Port Talbot County Borough. At the NE end of the Gnoll Estate on the hillside immediately W of the informal cascade.
Llygad Llwchwr ⓘ cave in United Kingdom
Ogof Afon Hepste ⓘ cave in Wales
Ogof Ap Robert ⓘ cave in Wales
Ogof Coed Cae ⓘ cave in Wales
Ogof Cynnes ⓘ cave in Wales
Ogof Dan y Lleuad Wen ⓘ cave in Wales
Ogof Fawr ⓘ cave in Wales
Ogof Fechan ⓘ cave in Wales
Ogof Ffynnon ⓘ cave in Wales
Ogof Ffynnon Ddu ⓘ cave in the Upper Swansea Valley in South Wales
Ogof Pwll Swnd ⓘ cave in Wales
Ogof Rhyd Sych ⓘ cave in Wales
Ogof Tarddiad Rhymney ⓘ cave in Wales
Ogof-Y-Ci ⓘ cave in Wales
Ogof-yr-Ardd ⓘ cave in Wales
Pant Mawr Pot ⓘ cave in Wales
Porth yr Ogof ⓘ river cave in Ystradfellte, Powys, Wales, United Kingdom
Porth-yr-Ogof ⓘ cave in Wales
Tunnel Cave Top ⓘ cave in Wales
Aber-gelli Colliery ⓘ coal mine in Wales
Aberaman Colliery ⓘ coal mine in Wales
Abercwmboi Colliery ⓘ coal mine in Wales
Aberdare Merthyr Colliery ⓘ coal mine in Wales
Abergorky Quarry III, Coal Level I ⓘ coal mine in Wales
Abergorky Quarry III, Coal Level II ⓘ coal mine in Wales
Abergwawr Colliery ⓘ coal mine in Wales
Aberpergwm Mine ⓘ coal mine in Wales
Ammanford Colliery, Ammanford ⓘ coal mine in Wales
Avon Colliery ⓘ coal mine in Wales
Bedlinog Colliery ⓘ coal mine in Wales
Bedwlwyn Colliery ⓘ coal mine in Wales
Birdshill Quarry ⓘ Site of Special Scientific Interest in Carmarthenshire, Wales
Black Grove Colliery ⓘ coal mine in Wales
Black Pins early ironstone workings ⓘ quarry in the UK
Blaen Ogwr ⓘ coal mine in Wales
Blaen-nant Colliery ⓘ coal mine in Wales
Blaen-nant Colliery, Iii ⓘ coal mine in Wales
Blaen-y-cwm Colliery ⓘ coal mine in Wales
Blaenant Colliery ⓘ coal mine in Wales
Blaencaerau Colliery ⓘ coal mine in Wales
Blaencorrwg Colliery ⓘ coal mine in Wales
Blaengarw Colliery ⓘ coal mine in Wales
Blaengrenig Coal Mine ⓘ coal mine in Wales
Bodringallt Colliery ⓘ coal mine in Wales
Boundary Level Colliery ⓘ coal mine in Wales
Brithdir And Cwmdu Colliery ⓘ coal mine in Wales
Bronbil Colliery And Tramway ⓘ coal mine in Wales
Bryn Defaid Coal Mine ⓘ coal mine in Wales
Bryn Defaid Mining Remains ⓘ coal mine in Wales
Bryn Pyllog, Opencast Mine ⓘ coal mine in Wales
Bryn-dewi Colliery ⓘ coal mine in Wales
Brynlliw Colliery ⓘ coal mine in Wales
Budd's Rock Colliery ⓘ coal mine in Wales
Bute Merthyr Colliery ⓘ Welsh coal mine active 1851-1926
Bwllfa Colliery ⓘ Welsh coal mine active 1856-1957
Cae-Sara Lead Mine ⓘ lead mine in Llangadog
Cae'r Mynydd Ventilation Furnace and Mine ⓘ coal mine in the UK
Caerau Colliery ⓘ former colliery in Caerau, Bridgend
Cambrian Colliery ⓘ former Welsh coal mine
Carno Pit ⓘ coal mine in Wales
Castle Pit, Troed-y-rhiw, Merthyr Tydfil ⓘ coal mine in Wales
Cefn Coed Colliery Museum ⓘ museum at former copper mine
Cefn Glas Pit ⓘ coal mine in Wales
Cefn-mawr Colliery ⓘ coal mine in Wales
Cefncoed Colliery ⓘ coal mine in Wales
Cilfrew Colliery ⓘ coal mine in Blaenhonddan, Neath Port Talbot, Wales, UK
Cilyrychen ⓘ quarry in Llandybie, Carmarthenshire
Cincoed Limestone Quarries and Kilns ⓘ quarry in the UK
Colliery Remains, Clydach Valley ⓘ coal mine in Wales
Corrwg Vale Colliery ⓘ coal mine in Wales
Craig-y-gigfran Coal Level, Aberdulais ⓘ coal mine in Wales
Craig-yr-Odyn Quarry ⓘ Slate quarry near Trap, Carmarthenshire, Wales, United Kingdom
Craigavon Colliery ⓘ coal mine in Wales
Cribarth Limestone Quarries and Tramroads ⓘ quarry in the UK
Crimea Colliery And Canal Quay, Ystalyfera ⓘ coal mine in Wales
Crug Farm Quarry ⓘ Site of Special Scientific Interest in Carmarthenshire, Wales
Cwm Cynon Colliery ⓘ coal mine in Wales
Cwm Garw, Coal Level ⓘ coal mine in Wales
Cwm Mawr Coal Level, Bft ⓘ coal mine in Wales
Cwm Merchon ⓘ lead mine in Cilycwm
Cwm Pelenna Colliery Ventilation Furnace ⓘ coal mine in the UK
Cwm Pit Colliery, Abercanaid ⓘ coal mine in Wales
Cwm-bargoed Pits ⓘ coal mine in Wales
Cwm-clydach Graigola Colliery ⓘ coal mine in Morriston, Swansea, Wales, UK
Cwm-glo Pit Coal Level ⓘ coal mine in Wales
Cwmbargoed Colliery ⓘ coal mine in Wales
Cwmcynon Colliery ⓘ coal mine in Wales
Cwmdare Colliery ⓘ coal mine in Wales
Cwmfelin Drift ⓘ coal mine in Wales
Cwmgwineu Colliery ⓘ coal mine in Wales
Cwmneol Colliery, Cwmaman ⓘ coal mine in Wales
Cymmer Colliery (Wales) ⓘ coal mine in the UK
Cynon Colliery ⓘ coal mine in Wales
Dan-y-deri Colliery ⓘ coal mine in Wales
Dare Colliery ⓘ coal mine in Wales
Darran Colliery ⓘ coal mine in Wales
Deep Dyffryn Colliery ⓘ coal mine in Wales
Dinas Middle Colliery ⓘ coal mine in Wales
Dowlais Top, Open Cast Mine ⓘ coal mine in Wales
Drum Colliery, Bft 3.1 ⓘ coal mine in Wales
Drum Colliery, Coal Level 3, B ⓘ coal mine in Wales
Drum Colliery, Level 1, Bft (3 ⓘ coal mine in Wales
Drum Colliery, Level 2, Bft (3 ⓘ coal mine in Wales
Drum Colliery, Shaft 1, Bft 3. ⓘ coal mine in Wales
Drum Colliery, Shaft 2, Bft 3. ⓘ coal mine in Wales
Drum Colliery, Shaft 3, Bft 3. ⓘ coal mine in Wales
Drum Colliery, Shaft 4, Bft 3. ⓘ coal mine in Wales
Dulais Resolven Colliery ⓘ coal mine in Wales
Dunraven Adare Colliery ⓘ coal mine in Wales
Dyffryn Main Colliery ⓘ coal mine in Wales
Dyffryn Rhondda Colliery ⓘ coal mine in Wales
Dyllas 1905 Coal Level I ⓘ coal mine in Wales
Dyllas Colliery ⓘ coal mine in Wales
Dynevor Main Colliery ⓘ coal mine in Wales
East Pit East Opencast Coal Site ⓘ coal mine in Wales
Emlyn Anthracite Colliery ⓘ colliery in Carmarthenshire, Wales, UK
Emlyn Colliery, Pen-y-groes ⓘ coal mine in Wales
Empire Colliery ⓘ coal mine in Wales
Felin Fach Colliery ⓘ coal mine in Wales
Felin Fran Colliery ⓘ coal mine in Wales
Ferndale Coal Mine Shafts ⓘ coal mine in Wales
Ferndale Colliery ⓘ coal mine in Wales
Ferndale Colliery ⓘ coal mine in Ferndale, Rhondda Cynon Taf, Wales, UK
Fernhill Collieries ⓘ coal mine in Wales
Fforch-Las Quarry, Glyncorrwg ⓘ stone quarry in Glyncorrwg, Neath Port Talbot
Fforchaman Colliery ⓘ coal mine in Wales
Fforchwen Coal Mine ⓘ coal mine in Wales
Fforest-goch Colliery ⓘ coal mine in Wales
Ffos-y-fran ⓘ coal mine in Wales
Ffos-y-fran Land Reclamation Scheme ⓘ Open-pit coal mine in south Wales
Fochrhiw Pits ⓘ coal mine in Wales
Fochriw Colliery ⓘ coal mine in Wales
Fochriw, Opencast Mine ⓘ coal mine in Wales
Four Feet Pit ⓘ coal mine in Wales
Gadlys New Pit ⓘ coal mine in Wales
Gadlys Old Pit ⓘ coal mine in Wales
Garn-goch Colliery No.3 ⓘ coal mine in Wales
Garth Merthyr Colliery ⓘ coal mine in Wales
Garth No.1 Colliery ⓘ coal mine in Wales
Garth No.3 Colliery ⓘ coal mine in Wales
Garw/Ffaldau Colliery ⓘ Welsh coal mine active in the 20th century
Garwed Brook Coal Level, Resolven ⓘ coal mine in Wales
Gelli Colliery ⓘ former colliery in South Wales
Gelligaer Coal And Iron Stone ⓘ coal mine in Wales
Gelligaer Coal And Ironstone ⓘ coal mine in Wales
George Colliery ⓘ coal mine in Wales
Gethin Pit No.1, Abercanaid ⓘ coal mine in Wales
Gethin Pit No.2, Abercanaid ⓘ coal mine in Wales
Glenavon Colliery ⓘ coal mine in Wales
Glenrhondda Colliery ⓘ coal mine in Wales
Glyn-dyrys Pit ⓘ coal mine in Wales
Glyn-dyrys Pits Level I ⓘ coal mine in Wales
Glyn-dyrys Pits Level Ii ⓘ coal mine in Wales
Glyn-dyrys Upper Level ⓘ coal mine in Wales
Glyn-dyrys Upper Pit ⓘ coal mine in Wales
Glyncastle Colliery ⓘ coal mine
Glyncastle Colliery ⓘ coal mine in Wales
Glyncorrwg Colliery, Afan Valley ⓘ coal mine in Wales
Gorllwyn Level ⓘ coal mine in Wales
Graig 1 Coal Pits ⓘ coal mine in Wales
Graig Coal Pits, Pentrebach ⓘ coal mine in Wales
Graig Colliery ⓘ coal mine in Wales
Graig Colliery & Brick Works ⓘ coal mine in Wales
Graig Colliery & Brick Works, Air Shaft ⓘ coal mine in Wales
Graig Colliery & Brick Works, Coal Level ⓘ coal mine in Wales
Graig Colliery & Brick Works, Coal Level Ii ⓘ coal mine in Wales
Graig Colliery & Brick Works, Drift Mine ⓘ coal mine in Wales
Graigola Colliery ⓘ coal mine in Wales
Great Pit, Llansamlet ⓘ coal mine in Wales
Grovesend Colliery ⓘ coal mine in Wales
Gwainclawdd Colliery ⓘ coal mine in Wales
Gwaunclawdd Colliery Level, Near Abercraf ⓘ coal mine in Wales
Gwernllwynchwith Colliery, Llansamlet ⓘ coal mine in Wales
Hendre-ladis Colliery ⓘ coal mine in Wales
Henllys Vale Coal Mine And Quarry,cwmllynfell ⓘ coal mine in Wales
High Dyffryn Colliery ⓘ coal mine in Wales
International Colliery ⓘ former colliery in Blaengarw, Bridgend
Iron Ore Scours and Patch Workings at Winch Fawr, Merthyr Tydfil ⓘ
Isaac Morgan's Pit, Merthyr Tydfil ⓘ coal mine in Wales
Lady Margaret Colliery ⓘ coal mine in Wales
Lefel Fawr Colliery, Abercraf ⓘ coal mine in Wales
Lefel Flook, Bft 1.5 ⓘ coal mine in Wales
Llethr Las, Coal Level I ⓘ coal mine in Wales
Llethr Las, Coal Level Ii ⓘ coal mine in Wales
Llethr Las, Coal Level Iii ⓘ coal mine in Wales
Llethr Las, Coal Level Iv ⓘ coal mine in Wales
Llethr Las, Coal Level V ⓘ coal mine in Wales
Llethr Las, Coal Level Vi ⓘ coal mine in Wales
Llethr Las, Coal Level Vii ⓘ coal mine in Wales
Llethr Las, Pit ⓘ coal mine in Wales
Llety-shenkin Colliery (upper) ⓘ coal mine in Wales
Lluest Colliery ⓘ coal mine in Pont-y-rhyl, Wales
Llwyn Du Colliery ⓘ coal mine in Wales
Llwynhelig Colliery ⓘ coal mine in Wales
Locomotive Type Steam Boiler, Blaen Rhondda ⓘ coal mine in the UK
Lower Colliers Level I ⓘ coal mine in Wales
Lower Colliers Level Ii ⓘ coal mine in Wales
Lower Colliers Level Iii ⓘ coal mine in Wales
Lower Colliers Post-1905 Level ⓘ coal mine in Wales
Lower Duffryn Pit, Cwmpennar ⓘ coal mine in Wales
Lower Dyffryn Colliery - Lower ⓘ coal mine in Wales
Lower Dyffryn Colliery - Upper ⓘ coal mine in Wales
Lower Fan Pit ⓘ coal mine in Wales
Lower Graigola Colliery ⓘ coal mine in Wales
Maclaren Colliery ⓘ coal mine in Wales
Maerdy Collieries No 3 Pit, Building Base ⓘ coal mine in Wales
Maerdy Collieries: No.1 Pit And No.2 Pit, Maerdy ⓘ coal mine in Wales
Maerdy Collieries: No.3 Pit And No.4 Pit, Maerdy ⓘ coal mine in Wales
Maerdy Colliery ⓘ coal mine in Wales
Main Colliery ⓘ coal mine in Wales
Mardy Colliery ⓘ Welsh coal mine active 1875-1990
Marine Colliery, Tonna ⓘ coal mine in Wales
Marsh Pit Colliery, Swansea ⓘ coal mine in Wales
Melyn Colliery ⓘ coal mine in Wales
Merthyrdare ⓘ coal mine in Wales
Middle Dyffryn Colliery ⓘ coal mine in Wales
Middle Fan Pit ⓘ coal mine in Wales
Middle Pit, Cwmpennar ⓘ coal mine in Wales
Miskin Colliery ⓘ coal mine in Wales
Mynachdy Colliery, Ynysybwl ⓘ coal mine in Wales
Mynydd Cefn-y-gyngon, Coal Level I ⓘ coal mine in Wales
Mynydd Cefn-y-gyngon, Coal Level Iii ⓘ coal mine in Wales
Mynydd Cefn-y-gyngon, Coal Level Iv ⓘ coal mine in Wales
Mynydd Cefn-y-gyngon, Coal Level V ⓘ coal mine in Wales
Mynydd Cefn-y-gyngon, Coal Level Vi ⓘ coal mine in Wales
Mynydd Cefn-y-gyngon, Coal Level Vii ⓘ coal mine in Wales
Mynydd Cefn-y-gyngon, Pit I ⓘ coal mine in Wales
Mynydd Cefn-y-gyngon, Trial Coal Level ⓘ coal mine in Wales
Mynydd Fochriw, Coal Level ⓘ coal mine in Wales
Mynydd Maerdy Coal Level Ii ⓘ coal mine in Wales
Mynydd Maerdy, Coal Level I ⓘ coal mine in Wales
Mynydd Tyntyle, Coal Level I ⓘ coal mine in Wales
Mynydd Tyntyle, Coal Level Xxxii ⓘ coal mine in Wales
Mynydd Tyntyle, Coal Level Ii ⓘ coal mine in Wales
Mynydd Tyntyle, Coal Level Iii ⓘ coal mine in Wales
Mynydd Tyntyle, Coal Level Iv ⓘ coal mine in Wales
Mynydd Tyntyle, Coal Level Ix ⓘ coal mine in Wales
Mynydd Tyntyle, Coal Level L ⓘ coal mine in Wales
Mynydd Tyntyle, Coal Level Li ⓘ coal mine in Wales
Mynydd Tyntyle, Coal Level Lii ⓘ coal mine in Wales
Mynydd Tyntyle, Coal Level Liii ⓘ coal mine in Wales
Mynydd Tyntyle, Coal Level Liv ⓘ coal mine in Wales
Mynydd Tyntyle, Coal Level Lix ⓘ coal mine in Wales
Mynydd Tyntyle, Coal Level Lv ⓘ coal mine in Wales
Mynydd Tyntyle, Coal Level Lvi ⓘ coal mine in Wales
Mynydd Tyntyle, Coal Level Lvii ⓘ coal mine in Wales
Mynydd Tyntyle, Coal Level Lviii ⓘ coal mine in Wales
Mynydd Tyntyle, Coal Level Lx ⓘ coal mine in Wales
Mynydd Tyntyle, Coal Level Lxi ⓘ coal mine in Wales
Mynydd Tyntyle, Coal Level Lxii ⓘ coal mine in Wales
Mynydd Tyntyle, Coal Level Lxiii ⓘ coal mine in Wales
Mynydd Tyntyle, Coal Level Lxiv ⓘ coal mine in Wales
Mynydd Tyntyle, Coal Level Lxv ⓘ coal mine in Wales
Mynydd Tyntyle, Coal Level Lxvi ⓘ coal mine in Wales
Mynydd Tyntyle, Coal Level Lxvii ⓘ coal mine in Wales
Mynydd Tyntyle, Coal Level Lxviii ⓘ coal mine in Wales
Mynydd Tyntyle, Coal Level V ⓘ coal mine in Wales
Mynydd Tyntyle, Coal Level Vi ⓘ coal mine in Wales
Mynydd Tyntyle, Coal Level Vii ⓘ coal mine in Wales
Mynydd Tyntyle, Coal Level Viii ⓘ coal mine in Wales
Mynydd Tyntyle, Coal Level X ⓘ coal mine in Wales
Mynydd Tyntyle, Coal Level Xi ⓘ coal mine in Wales
Mynydd Tyntyle, Coal Level Xii ⓘ coal mine in Wales
Mynydd Tyntyle, Coal Level Xiii ⓘ coal mine in Wales
Mynydd Tyntyle, Coal Level Xiv ⓘ coal mine in Wales
Mynydd Tyntyle, Coal Level Xix ⓘ coal mine in Wales
Mynydd Tyntyle, Coal Level Xl ⓘ coal mine in Wales
Mynydd Tyntyle, Coal Level Xli ⓘ coal mine in Wales
Mynydd Tyntyle, Coal Level Xlii ⓘ coal mine in Wales
Mynydd Tyntyle, Coal Level Xliii ⓘ coal mine in Wales
Mynydd Tyntyle, Coal Level Xliv ⓘ coal mine in Wales
Mynydd Tyntyle, Coal Level Xlix ⓘ coal mine in Wales
Mynydd Tyntyle, Coal Level Xlv ⓘ coal mine in Wales
Mynydd Tyntyle, Coal Level Xlvi ⓘ coal mine in Wales
Mynydd Tyntyle, Coal Level Xlvii ⓘ coal mine in Wales
Mynydd Tyntyle, Coal Level Xlviii ⓘ coal mine in Wales
Mynydd Tyntyle, Coal Level Xv ⓘ coal mine in Wales
Mynydd Tyntyle, Coal Level Xvi ⓘ coal mine in Wales
Mynydd Tyntyle, Coal Level Xvii ⓘ coal mine in Wales
Mynydd Tyntyle, Coal Level Xviii ⓘ coal mine in Wales
Mynydd Tyntyle, Coal Level XX ⓘ coal mine in Wales
Mynydd Tyntyle, Coal Level Xxi ⓘ coal mine in Wales
Mynydd Tyntyle, Coal Level Xxii ⓘ coal mine in Wales
Mynydd Tyntyle, Coal Level Xxiii ⓘ coal mine in Wales
Mynydd Tyntyle, Coal Level Xxiv ⓘ coal mine in Wales
Mynydd Tyntyle, Coal Level XXIX ⓘ coal mine in Wales
Mynydd Tyntyle, Coal Level Xxv ⓘ coal mine in Wales
Mynydd Tyntyle, Coal Level Xxvi ⓘ coal mine in Wales
Mynydd Tyntyle, Coal Level Xxvii ⓘ coal mine in Wales
Mynydd Tyntyle, Coal Level Xxviii ⓘ coal mine in Wales
Mynydd Tyntyle, Coal Level Xxx ⓘ coal mine in Wales
Mynydd Tyntyle, Coal Level Xxxi ⓘ coal mine in Wales
Mynydd Tyntyle, Coal Level Xxxiii ⓘ coal mine in Wales
Mynydd Tyntyle, Coal Level Xxxiv ⓘ coal mine in Wales
Mynydd Tyntyle, Coal Level Xxxix ⓘ coal mine in Wales
Mynydd Tyntyle, Coal Level Xxxv ⓘ coal mine in Wales
Mynydd Tyntyle, Coal Level Xxxvi ⓘ coal mine in Wales
Mynydd Tyntyle, Coal Level Xxxvii ⓘ coal mine in Wales
Mynydd Tyntyle, Coal Level XXXVIII ⓘ coal mine in Wales
Mynydd-newydd Colliery ⓘ coal mine in Wales
Mynydd-y-drum Coal Patch 1, Bf ⓘ coal mine in Wales
Mynydd-y-drum Coal Patch 2, Bf ⓘ coal mine in Wales
Nant Cwm Gau, Coal Level ⓘ coal mine in Wales
Nant Melin Colliery ⓘ coal mine in Wales
Nant-y-bwlch, Coal Level I ⓘ coal mine in Wales
Nant-y-bwlch, Coal Level Ii ⓘ coal mine
Nant-y-bwlch, Coal Level Ii ⓘ coal mine in Wales
Nant-y-bwlch, Coal Level Iii ⓘ coal mine
Nant-y-bwlch, Coal Level Iii ⓘ coal mine in Wales
Nant-y-bwlch, Coal Level Iv ⓘ coal mine in Wales
Nant-Y-Mwyn Deep Boat Mine ⓘ lead mine in Llanfair-ar-y-bryn
Nantewlaeth Colliery ⓘ coal mine in Wales
Nantewlath Coal Mine Ruins ⓘ coal mine in Wales
Nantwen Colliery ⓘ coal mine in Wales
Ndinas Fawr Lead Level ⓘ lead mine in Cilycwm
Neuadd Fawr Level Lead ⓘ lead mine in Cilycwm
New Cross Hands Colliery, Cross Hands ⓘ coal mine in Wales
New Dyffryn Colliery ⓘ coal mine in Wales
New Gored Merthyr Colliery ⓘ coal mine in Wales
New Gorsllan Colliery ⓘ coal mine in Wales
New Tredegar Colliery ⓘ former colliery in New Tredegar
New Wernddu Colliery ⓘ coal mine in Wales
Nixon's Navigation Colliery ⓘ former coal mine in Mountain Ash
No.1 Pit (dowlais) ⓘ coal mine in Wales
No.2 Ferndale Pit ⓘ coal mine in Wales
No.4 Ferndale Pit ⓘ coal mine in Wales
No.6 Pit (dowlais) ⓘ coal mine in Wales
North Rhondda Colliery ⓘ coal mine in Wales
Ochr-y-mynydd Level Iv ⓘ coal mine in Wales
Ochr-y-mynydd Level Ix ⓘ coal mine in Wales
Ochr-y-mynydd Level V ⓘ coal mine in Wales
Ochr-y-mynydd Level Vi ⓘ coal mine in Wales
Ochr-y-mynydd Level Vii ⓘ coal mine in Wales
Ochr-y-mynydd Level Viii ⓘ coal mine in Wales
Ochr-y-mynydd Level X ⓘ coal mine in Wales
Ochr-y-mynydd Level Xi ⓘ coal mine in Wales
Ochr-y-mynydd Tramming Level I ⓘ coal mine in Wales
Ochyr-y-mynydd Coal Level I ⓘ coal mine in Wales
Ogilvie Colliery ⓘ former coal mine in Deri, Wales
Old Coal Levels To West Of Glyn-gwilym ⓘ coal mine in Wales
Old Colliery ⓘ coal mine in Wales
Old Colliery ⓘ coal mine
Old Dyffryn Colliery ⓘ coal mine in Wales
Old Dyffryn Colliery ⓘ coal mine
Onllwyn Colliery ⓘ coal mine in Wales
Onllwyn Colliery, Coal Level 2 ⓘ coal mine in Wales
Onllwyn Colliery, Coal Level 3 ⓘ coal mine in Wales
Onllwyn Colliery, Coal Level 4 ⓘ coal mine in Wales
Onllwyn Colliery, Level 1, Bft ⓘ coal mine in Wales
Padell-y-bwlch, Coal Level I ⓘ coal mine in Wales
Padell-y-bwlch, Coal Level Ii ⓘ coal mine in Wales
Pantyffynnon Coal Mine ⓘ coal mine in Wales
Park Colliery ⓘ coal mine in Wales
Pemrhiw Rhaiadr Lead Mines ⓘ lead mine in Cilycwm
Pen Milan Quarries ⓘ stone quarry in Glyn Tarell, Powys
Pen-cae Level Ii ⓘ coal mine in Wales
Pen-y-coedcae Level (east) ⓘ coal mine in Wales
Pen-y-coedcae Level I ⓘ coal mine in Wales
Pen-y-darren Colliery, Merthyr Tydfil ⓘ coal mine in Wales
Pen-y-darren Disused Coal Pits, Merthyr Common East, Ne Of Pentrebach ⓘ coal mine in Wales
Pen-Y-Garreg ⓘ lead mine in Talley
Pendyrys Colliery ⓘ coal mine in Wales
Penrhiw-ceibr Colliery ⓘ former colliery in Penrhiwceiber
Penrhiwceibr Colliery ⓘ coal mine in Wales
Pentre Colliery (Glamorgan, Wales) ⓘ coal mine in the UK
Pentre Colliery, Pyle ⓘ coal mine in Wales
Pentreclwydau Colliery ⓘ coal mine in Wales
Pentregwenlais quarry ⓘ Slate quarry near Carmel, Wales, United Kingdom. Now in the Carmel National Nature Reserve
Pentwyn Colliery ⓘ coal mine in Wales
Penwaen Coal Level ⓘ coal mine in Wales
Plas-y-coed Coal Mine ⓘ coal mine in Wales
Pwll Priddog Level (Lead) ⓘ lead mine in Cilycwm
Pwllfaron Colliery ⓘ coal mine in Wales
Raslas Pit ⓘ coal mine in Wales
Rhondda Main Colliery ⓘ coal mine in Wales
Rhondda Merthyr Colliery ⓘ coal mine in Wales
Rhymney Hill, Coal Mine ⓘ coal mine in Wales
Rhymney Merthyr Colliery ⓘ coal mine in Wales
Rock Colliery, Rheola Forest ⓘ coal mine in Wales
Scott's Pit, Llansamlet, Swansea ⓘ coal mine in Wales
South Dyffryn Coal Pits And Level ⓘ coal mine in Wales
South Tunnel Pit ⓘ coal mine in Wales
St John's Colliery, Maesteg ⓘ coal mine in Wales
Taff Colliery ⓘ coal mine in Wales
Taff Merthyr Colliery, Bedlinog ⓘ coal mine in Wales
Tal-y-fan-fach Coal Mine ⓘ coal mine in Wales
Tal-y-wendda Drift Colliery ⓘ coal mine in Wales
Tarenni Colliery ⓘ coal mine in the UK
Terrace Colliery ⓘ coal mine in Wales
Tir-ffordd Colliery, Llangyfelach ⓘ coal mine in Wales
Tir-y-dail Colliery ⓘ coal mine in Wales
Tirherbert Colliery ⓘ coal mine in Wales
Tirherbert Colliery, Drift Entrance ⓘ coal mine in Wales
Ton-pentre Colliery ⓘ coal mine in Wales
Tor-cefn Colliery Mine Workings ⓘ coal mine in Wales
Tower (old) Colliery, Hirwaun ⓘ coal mine in Wales
Tower Colliery ⓘ Historic Welsh coal mine active until 2008
Tower Colliery Opencast Mine Workings ⓘ coal mine in Wales
Tower Drift Mine, Hirwaun ⓘ coal mine in Wales
Tower Graig Level, Building I ⓘ coal mine in Wales
Tower Graig Level, Building Ii ⓘ coal mine in Wales
Tower Graig Level, Hirwaun ⓘ coal mine in Wales
Tre-aman Colliery ⓘ coal mine in Wales
Trefil Quarries North ⓘ quarry in the UK
Trelewis Drift Mine, Bedlinog ⓘ coal mine in Wales
Trewern Coal Mine ⓘ coal mine in Wales
Tunnel Colliery ⓘ coal mine in Wales
Tunnel Pits ⓘ coal mine in Wales
Twyn Canwyllyr, Coal Level ⓘ coal mine in Wales
Ty Trist Colliery ⓘ coal mine in Wales
Ty-draw Colliery ⓘ coal mine in Wales
Ty-fry, Coal Level ⓘ coal mine in Wales
Ty-trist Colliery ⓘ coal mine in Wales
Ty'n-y-waun Colliery ⓘ coal mine in Wales
Tyle-coch Colliery ⓘ coal mine in Wales
Tylorstown No.8 Colliery ⓘ former coal mine in Rhondda Cynon Taf, Wales
Tyn-y-waun, Coal Level ⓘ coal mine in Wales
Tynewydd Colliery ⓘ coal mine in Wales
Tynybedw Colliery ⓘ former coal mine
Tyrau Colliery ⓘ coal mine in Wales
Upper Dyffryn Colliery ⓘ coal mine in Wales
Upper Fan Pit ⓘ coal mine in Wales
Upper Graigola Colliery ⓘ coal mine in Wales
Waun-y-coed Colliery, Pontardawe ⓘ coal mine in Wales
Welsh Main Colliery ⓘ coal mine in Wales
Welsh Main Colliery, Glyncorrwg ⓘ coal mine in Wales
Werfa Colliery ⓘ coal mine in Wales
Wernddu Colliery ⓘ coal mine in Wales
Wernffraith Colliery ⓘ coal mine in Wales
West Colliery, Hendy ⓘ coal mine in Wales
West Merthyr Colliery ⓘ coal mine in Wales
Whitworth Colliery ⓘ coal mine in Wales
Whitworth Colliery ⓘ coal mine
Winch Fawr Level V ⓘ coal mine in Wales
Windber Colliery ⓘ coal mine in Wales
Wyndham Pit ⓘ coal mine in Wales
Y Darren Widdon And Darren Fach Mining Landscape, Ystalyfera ⓘ coal mine in Wales
Ynys-arwed Colliery ⓘ coal mine in Wales
Ynys-Faio Colliery ⓘ former colliery
Ynysarwed Colliery ⓘ former coal mine in the Vale of Neath
Ynyshir Mineworkings ⓘ former coal mine in Ynyshir
Ysgubor-wen Balance Pit ⓘ coal mine in Wales
Ysguborwen Coal Mine, Ammanford ⓘ coal mine in Wales
Ystradgynlais Colliery ⓘ former colliery in Ystradgynlais
Morfa Colliery ⓘ former colliery at Port Talbot
Cwmaman Colliery ⓘ former colliery near Aberdare
Court Herbert Colliery ⓘ former colliery near Neath
Gorsgoch Collieries ⓘ former coal mine in Crosshands
Glamorgan Colliery ⓘ former coal mine at Llwynypia
Cilely Colliery ⓘ former colliery in South Wales
Seven Sisters Colliery ⓘ former coal mine in South Wales
Gwaun-cae-gurwen Colliery ⓘ former colliery in Neath Port Talbot
Coegnant Colliery ⓘ former colliery in Nantyffyllon
Lady Windsor Colliery ⓘ coal mine in Wales
McLaren Colliery ⓘ former colliery in Abertysswg
Cwmgwrach Colliery ⓘ former colliery in Blaengwrach
Bryn Varteg Colliery ⓘ former colliery in Ystalyfera
Abernant Colliery ⓘ coal mine in South Wales (1954–1988)
South Wales Miners' Museum ⓘ mining museum in Port Talbot, South Wales
Abernant Tunnel ⓘ railway tunnel in the UK
Ashford tunnel N Portal (Monmouthshire and Brecon Canal) ⓘ Grade II listed building in Powys. Adjacent to B4558, W of Ashford.
Ashford Tunnel S Portal (Monmouthshire and Brecon Canal) ⓘ Grade II listed building in Powys. Adjacent to the B4558, NE of Ashford Cottage.
Cwmcerwyn Tunnel ⓘ railway tunnel in the UK
Gelli Tunnel ⓘ railway tunnel in the UK
Gyfylchi Tunnel ⓘ railway tunnel in the UK
Morlais Tunnel ⓘ railway tunnel in the UK
Penllergaer Tunnel ⓘ railway tunnel in the UK
Quakers Yard Tunnel ⓘ railway tunnel in the UK
Rhondda Tunnel ⓘ railway tunnel in the UK
Subway Under Railway ⓘ Grade II listed building in Neath Port Talbot County Borough.
Sugar Loaf Tunnel (Wales) ⓘ railway tunnel in the UK
Tal-y-llyn Railway Tunnel ⓘ Grade II listed building in Powys. In the hamlet of Tal-y-llyn in a garden of a house converted from the former station.
Torpantau Tunnel ⓘ railway tunnel in Tal-y-bont on Usk, Wales
Tunnel carrying Brynich stream under Brecon & Abergavenny Canal (partly in Brecon community) ⓘ Grade II listed building in Powys. Situated some 900m along the canal W from Cefn Brynich Lock, on border with Brecon community.
