Bryn Celli Ddu

Bryn Celli Ddu is a Late Neolithic passage grave on the Welsh island of Anglesey, near Llanddaniel Fab. Its name means 'the mound in the dark grove.'[1] The site was excavated between 1928 and 1929.[1] Visitors can enter through a stone passage to a central burial chamber containing a mysterious pillar and a reproduction of the Pattern Stone, carved with sinuous serpentine designs.[1] Originally constructed as a henge with a stone circle before becoming a chambered tomb, the site may have been used to plot the summer solstice.[1] It is now a Scheduled Monument in the care of Cadw.[1]