Tony and the Time Team climb a remote Herefordshire hill to investigate one of the biggest prehistoric sites ever featured. Was Dinmore Hill the site of a vast Iron Age hill fort? Needless to say Stewart doesn't think so. He is going with a much earlier cross-ridge dyke. To prove it one way or the other they need dateable finds. But the dig is hampered by torrential rain. Despite this they uncover a huge, magnificent ditch, which must have been dug by thousands of people during the Iron Age. The team are joined by historian Bettany Hughes, Hereford county archaeologist Keith Ray and environmental archaeologist Mike Allen.

• Tim Taylor

• Suzannah Lipscomb
• Tony Robinson
• Phil Harding