There's an island-ish round area of stones in Loch Migdale - could it be a crannog? 200 meters away on the banks is a small (12 m diameter) circular feature - is it a henge? Time Team rounds up some experts on the prehistoric and finds out. They set up a suction dredge to investigate two areas of the loch feature, and find wonderfully preserved timber, proving that it's a built structure and thus a crannog. GPS surveying and a tip from a local farmer finds the causeway, now underwater, leading to it Trenches within the henge show that the entrance and wooden posts within it pointed towards notable features in the landscape. Stewart looks for the find site of the Migdale Hoard.

• Tim Taylor

• Suzannah Lipscomb
• Tony Robinson
• Phil Harding