Newgrange (Brú na Bóinne)

A Neolithic passage tomb built around 3200 BC, older than Stonehenge and the Egyptian pyramids, a great mound with a ring of carved kerbstones. At dawn around the winter solstice, sunlight shines down the passage into the inner chamber. The tour recreates this with a lamp.

Newgrange and Knowth can only be visited on tours from the Brú na Bóinne Visitor Centre; book ahead in summer. It's about an hour north of Dublin. The Hill of Tara, seat of the ancient high kings, is nearby.