Heliopolis

(hēˌlē-ŏpˈə-lĭs)

1. An ancient city of northern Egypt in the Nile River delta north of modern Cairo. It was the center of worship of the sun god Ra until the rise of Thebes (c. 2100 B.C.). Its importance as a historical repository with famed schools of philosophy and astronomy declined after the founding of Alexandria in the fourth century B.C. Two of its obelisks, both known as Cleopatra's Needle, are now in London and in New York City's Central Park.
2. See Baalbek.