See the Standing Stones at Avebury then climb to The Ridgeway and follow it south to near the car park at Overbury (alternative starting point).
The track back to Avebury via Manor Farm is likely to be challenging, particularly during or just after wet weather!
A safer option might be to start from Overton Hill, go north along the Ridgeway to Overton Down then turn west along Green Street and on to Avebury for lunch and a wander around the museum (charge – NT members free) and stone circle. Then return the same way. Even this has the usual Ridgeway Ruts to cope with.
To the east of the Ridgeway are Sarsen Stones. They are also known as Grey Wethers - as wether being a sheep. The idea is that the field looks to be full of grey sheep.