The Welsh name Llanbadrig translates as "Church of Saint Patrick" and there is indeed a Church of St. Patrick on the coast near Cemaes. It is said to have been founded in440CE by St. Patrick himself.
Local legend states that Patrick was shipwrecked on the small nearby island of Ynys Badrig (Patrick's Isle, also known as Middle Mouse), which can be seen from the stile in the churchyard wall.
During the building preparations for Wylfa nuclear power station in 1964, workmen became bothered not by the hard graft – but the fact that their task was being hampered by the appearance of a ghost! Whilst they were excavating a tunnel at the site of Galan Ddu, the Black Bank, the number reported citing the apparition of a woman in white, and hummed a tune! According to Coxe, this caused a number of workmen to quit their jobs.
The suggested cause of the apparition is an interesting one. Galan Ddu was bought by the noted New Zealand Opera singer Rosie Buckman (born 16 March 1881 – died 30 December 1948) as a summer retreat for herself, husband and mother-in-law. Apparently the casket containing her ashes were disturbed during the excavations, removed and reinterred at Llanbadrig Church, Cemaes. According to other sources, it seems the apparition is usually seen in July or August wondering the power station on the cliff tops, but allegedly coincides with a time of Buckman's summer holidays.