The site dates back to 3400BC and consists of a henge, a long barrow, various earthworks and several stone circles. It includes the largest stone circle in Europe, which encircles the village of Avebury - the only village in the world within a stone circle. And yet Avebury is a working village with a manor house, farms, a post office and a pub, among other buildings. The site was saved only in the 20th century, since, like the fate of old structures around the world, the local population had gradually been clearing the land for farming and using the stones for building. Fortunately now it is a World Heritage protected site.
Here are some pics:
The dovecote at the manor
Silbury Hill is a chalk mound adjoining the Avebury circle and the Kennet Long Barrow. It is the tallest prehistoric man-made mound in Europe and one of the largest in the world, the same height as some of the Giza pyramids. Its purpose is still unknown, although it seems to have been built over many centuries and it may simply have been the waste from the earthworks, weathered to its present shape. But, at some 5,000 years old, it remains a somehow moving structure in the middle of the bare countryside.