The Fortress in the Lake

S1 E4: The Time Team travel to Brecon Beacons in Wales. They have come to investigate a small man-made island in the middle of Llangorse Lake. Locals tell many strange legends here, including hearing the sounds of Church bells echoing across the body of water at night. The team wants to know who built the island. They try to find evidence to support the stories and how it eventually fell into disuse.