In Roman mythology
, the goddess Egeria
("of the black poplar") was a goddess of birth, wisdom and one of the Camenae
. She was married to Numa Pompilius
, second king of Rome
and taught him matters relating to being a wise and just king.
When Numa Pompilius died, she changed him into a well, located in the forest of Aricia, holy to Diana, in Latium.