The Ichthus Stone is to be found against the west wall inside the church of Llanbadrig near Cemaes Bay, on the north coast of Anglesey, North Wales.

The stone was hidden beneath the plaster of the church for many years until in 1884 renovations exposed the stone. It carries the early Christian symbols of the fish and the palm tree, the latter signifying Jerusalem. Similar stones have been found in the catacombs in Rome, and for some time it was thought the stone was of a foreign origin.

But the inscriptions are probably representative of the 9th to the 11th Century gravestones of which there are several to be found in Anglesey.

Following investigation by the Department of Geology at Leicester University it is now accepted as being an Anglesey stone that has been used for more than one purpose. It would initially have been used as a standing stone (a similar stone believed to be some 4500 years old was found in the middle of a large field near Llanerchymedd), before early christians claimed the stone for themselves around the 10th Century.