Stonehenge at sunset. Silhouette of Stonehenge, a standing stone circle on Salisbury Plain in Wiltshire, England. The first henge was built on this site over 5000 years ago. The circle of massive stones present today was erected around 2000 BC by neolithic people. The stones of the outer ring are six metres high and the circle measures 30 metres across. Originally stone lintels would have formed a circle on top of the outer ring of stones, though few remain in place today. The stones are designed to be aligned with the rising midsummer sun, probably to enable astronomical predictions to be made. Stonehenge is a UNESCO World Heritage site.