Newgrange

Newgrange is a prehistoric monument in County Meath in Ireland, located on a rise overlooking the River Boyne, eight kilometres west of the town of Drogheda. It is an exceptionally grand passage tomb built during the Neolithic Period, around 3200 BC, making it older than Stonehenge and the Egyptian pyramids. Newgrange is the main monument in the Brú na Bóinne complex, a World Heritage Site that also includes the passage tombs of Knowth and Dowth, as well as other henges, burial mounds and standing stones.Newgrange consists of a large circular mound with an inner stone passageway and cruciform chamber.

Source: Wikipedia