AD 448

Alphin Mc. Eochaid, king of Dublin, and his subjects, were converted to the christian faith by the preaching of St. Patrick, and baptized in a fountain called after that missionary's name, St. Patrick's well, on the south side of the city, near where the steeple of the church dedicated to him now stands; which well (we are told by archbishop Usher) (Primord. P 863) was a little before the year 1639, shut up and inclosed within a private house.

From the Annals of Dublin