The Royal Observatory, Greenwich, London founded in 1675. The site of the Prime Meridian as well as the origin of Greenwich Mean Time, now the Observatory's historic buildings house a museum of astronomy, navigation and timekeeping as well as the Weller Galleries of modern astronomy and the award winning Peter Harrison Planetarium.
At ground level, the ruins of Stonehenge appear somewhat random and chaotic, but a view from the air reveals the monument's circular order. The site started out modestly around 3100 B.C. as a wide ring of wood posts surrounded by a ditch and bank. The familiar enormous rock slabs, some brought from hundreds of miles away, were added to the interior over a period of about 1,500 years.
Silbury Hill, Avebury. The largest man-made mound in Europe, mysterious Silbury Hill compares in height and volume to the roughly contemporary Egyptian pyramids. Probably completed in around 2400 BC, it apparently contains no burial. Though clearly important in itself, its purpose and significance remain unknown. There is no access to the hill itself. Distance from Shaftesbury to Avebury is 42 miles More