At winter solstice, the shortest day of the year in the northern hemisphere, the sun shines down this 5,000 year old passage and hits the back wall. The Neolithic chambered mound lies about 500m off the Brittany coast, on the small island of Gavr'inis.

These beautifully carved stone slabs support a 17-tonne stone slab acting as the roof of the tomb. At the time of its construction, c. 3500 B.C., the island was still connected with the mainland, and is today only accessible by boat.