Rising abruptly from the fields just south of Avebury, 40m-high Silbury Hill is the largest artificial earthwork in Europe, comparable in height and volume to the Egyptian pyramids. It was built in stages from around 2500 BC, but the precise reason for its construction remains unclear. Direct access to the hill isn't allowed, but you can view it from a lay-by on the A4.

For more atmospheric views, walk from Avebury village – head through the main car park, cross the road, then pick up the footpath south across the fields (3 miles return) to the hill's north side.