'Three stones' is the translation from Welsh of Trellech: tri is three, llech is a flat stone. There are many legends about these stones which stand in a field just outside this Monmouthshire village. Formed from a local stone known as 'pudding stone', which looks like very rough concrete but is in fact volcanic lava, the stones are 9, 12 and 15 feet high, and are thought to date from the middle to late Neolithic (New Stone Age) period, around 9500 BC.