New lighting installed at world's largest excavated prehistoric cavern

Great Orme Mines in Llandudno is having atmospheric lighting fitted in its roughly 50ft-high prehistoric chamber ahead of the 2026 season, with mines manager and qualified electrician Nick Jowett using a Tyrolean traverse to access fixtures.

Great Orme Mines in Llandudno is having new atmospheric lighting installed in its largest prehistoric excavated chamber ahead of the 2026 season. The work is being led by mines manager Nick Jowett, who is also a qualified electrician and experienced rope access technician. To reach fixtures across the roughly 50ft-high chamber he used a Tyrolean traverse while suspended between points. The team says the lighting is revealing archaeological and geological features in new ways and that they are exploring ways to make future maintenance easier. Site details: - The chamber is about 50ft high and is reported as the world's largest prehistoric underground excavation. - New atmospheric lighting systems are being fitted for the 2026 visitor season. - Mines manager Nick Jowett used a Tyrolean traverse to reach and test lights in hard-to-access areas. - Excavations beginning in the late 1980s uncovered more than five miles of prehistoric tunnels, with estimates that less than half have been found. - Studies suggest mining at the site began around 4,000 years ago, and more than 35,000 animal bones have been recovered. Summary: The new lighting is changing how underground features are seen and forms part of preparations for the site's reopening and visitor season. Ropework and surface maintenance have also been carried out ahead of a March reopening, and the mine has recently become a Verified Conwy Tourism Ambassador Business.