Bryn Celli Ddu - an ancient henge

Bryn Celli Ddu is an ancient site in Anglesey.

Once Bryn Celli Ddu was an ancient henge but it is believed sometime around 3000BC, the site was changed into a cairn. The original standing stones were capped and covered with earth to become a grave. However it is possible, there was always a central cairn and the standing stones ringed the cairn. Like other prehistoric graves of the British isles, it's a passage grave.

What isn't in doubt is that Bryn Celli Ddu is a superb example of a late Neolithic passage grave in the European Atlantic tradition. It was first excavated and partly restored in the mid to late 1920s by W J Hemp. It comprises an outer circular stone kerb c. 26m diameter, with an inner stone arc, both of which encircle a simple passage tomb with the entrance on the east side.

Bryn Celli Ddu, means the mound in the dark grove in Welsh, featured a stone circle surrounded by rings of earthworks.


In 1906, Sir Joseph Norman Lockyer, published the first systematic study of megalithic astronomy and argued that Bryn Celli Ddu marked the summer solstice. At the time, the notion that neolithic people could possess astronomical knowledge was ridiculed but the idea was confined to the margins of scientific and
archaeological thinking.

Some years were to pass, however, before Lockyer was proved correct. Exhaustive research by Christopher Knight and Robert Lomas in 1997- 98 showed Bryn Celli Ddu and other sites were aligned with astronomical events.

Knight and Lomas published their results published in 'Uriels Machine.' which delved into Anglesey's druidic past and Freemasonry.

In 2005, further research of the alignment was undertaken by Dr Steve Burrow, Curator of Neolithic Archaeology at The National Museum and Galleries Wales, who decided to visit the site to see if the solstice alignment theory was correct.

“There was no need for me to stay all night – although I know people who say they have – dawn is a pretty well-timetabled event, so I just checked a newspaper and turned up an hour before the sun was due. It's stunning.

First there is a sparkle through the trees, then the sun rises up and it's exhilarating. The rays come into the chamber and light up a quartz-rich stone at the back of the tomb; it’s perfectly lined up. The quartz sparkles”.