Greystones is located south of the site of an ancient castle of the Barony of Rathdown. There was a hamlet which, like Rathdown Castle, was known as Rathdown, and which appeared on a 1712 map. This site occupied an area now known as the Grove, north of Greystones harbour, but only the ruins of a chapel, St. Crispin's Cell, survive. Greystones is a much more recent settlement and is first mentioned in "Topographia Hibernica", a 1795 publication. Here it is described as a "noted fishing place four miles beyond Bray."