🇬🇧 United Kingdom · Megalith
Arthur's Stone, Gower (Maen Cetti)
Early Neolithic to Early Bronze Age · Severn-Cotswold / Gower Neolithic
Gower's 40-tonne conglomerate portal dolmen on Cefn Bryn ridge — largest capstone in Wales, split 1693.
🇬🇧 United Kingdom · Megalith
Trethevy Quoit
Early Neolithic · East Cornwall Early Neolithic
East Cornwall's tallest quoit — 2.4 m uprights supporting capstone 3 m high with internal divider and rear window.
🇬🇧 United Kingdom · Megalith
Dyffryn Ardudwy Burial Chamber
Early to Middle Neolithic · Irish Sea Neolithic
Double portal dolmen in Snowdonia foothills with two capstones sharing a mound near Cardigan Bay.