This week’s episode turns to King Arthur who according to legend was Britain's greatest king. He led his Knights of the Round Table from Camelot, a vast, spectacular castle built on a hill, and was supposed to have bravely fought AngloSaxon invaders and united the country. But there's very little evidence he reallyexisted. In the 1960's a team of archaeologists, led by Leslie Alcock, set out to prove the myth was real. After five summers digging where tradition had the location Camelot to be, a hill just off the A303 in South Cadbury, Somerset they discovered Dark Age fortifications dated exactly to the time King Arthur was supposed to have lived, and a great hall, suitable for a King or leader of some kind. Proof, they believed, that Arthur, or someone very like him existed.

• Laura Frances-Martin