Nymphaeums are monuments dedicated to nymphs. Percy Jackson, Piper McLean, and Jason Grace enter one under a building in The Mark of Athena. It was a shrine to the nine original nymphs who raised Zeus as a baby and concealed him away from Kronos.
Function and Purpose[]
These monuments were originally natural grottoes, which tradition assigned as habitations to the local nymphs. They were sometimes so arranged as to furnish a supply of water, as at Pamphylian Side.