Castell Henllys (Welsh, "castle of the old court") is an important archaeological site in north Pembrokeshire, Wales, on the A487 road between Newport and Cardigan, in the parish of Nevern. The Iron Age hillfort has been the subject of an ongoing excavation for more than twenty years, accompanied by an exercise in reconstruction archaeology whereby experiments in prehistoric farming have been practised. Four roundhouses and a granary have been reconstructed on their original Iron Age foundations, some 2,000 years old, the only site in Britain where this has been done. Historic UK say: During the summer the site provides training for young archaeologists and is a popular visitor attraction. It is owned by Pembrokeshire Coast National Park. See also List of hillforts in Wales Butser Ancient Farm Weald and Downland Living Museum References External links Castell Henllys website Celtic roundhouses at Castell Henllys Castell Henllys at Gathering the Jewels Photoraphs of Castell Henllys and surrounding area on Geograph Hillforts in Pembrokeshire Museums in Pembrokeshire Open-air museums in Wales Prehistoric sites in Pembrokeshire Experimental archaeology Archaeological museums in Wales