Italian Writer's Guide to Unknown Rome

The spirit of Nymph Egeria, divine consort of King Numa Pompilius, still lingers in this sacred grove,
in the nympheum created by the great senator Herodes Atticus in an area of his magnificent villa.
A picturesque sight, rich in waters and greenery, where mythology seems to enter into the real world.

A tale was told in ancient ages of a Roman king, Numa Pompilius, who had fallen in love with a nymph of the waters, Egeria. Egeria instructed Numa in the sacred religion of Rome, by teaching him laws and rituals.
The place where their encounters took place was celebrated by one of the richest men in the Roman empire: Herodes Atticus, who owned a vast villa in what today is the Valle della Caffarella, near the Appia Antica. He set up a nympheum dedicated to the name of Egeria, with a porticoed walk and delicious water features for the refreshment of the wealthy senator and his selected friends.
In Grand Tour times, the sight was considered so picturesque, lost as it was in the Roman Campagna, as to enchant visitors, with the words in mind of Juvenal: "Nymph of the Spring! More honour’d hadst thou been, if, free from art, an edge of living green, thy bubbling fount had circumscribed alone, and marble ne’er profaned the native stone..."