Daphni or Dafni, is an 11th-century Byzantine monastery 11 km north-west of central Athens in the suburb of Chaidari, south of Athinon Avenue. It is situated near the forest of the same name, on the Sacred Way that led to Eleusis. The forest covers about 15 to 20 km².

The Daphni Monastery was founded about the turn of the 6th century, Christianizing the site of the Sanctuary of Apollo Daphnaios that had been desecrated by the Goths in 395, and reusing the Ionic columns of the ancient temple of Apollo in its portico; only one remains, the others having been removed to London by Thomas Bruce, 7th Earl of Elgin.

The principal church (katholikon), a fine monument of the 11th-century Byzantine art, is a cross-in-square church of the octagonal type surmounted by a broad and high dome. The church houses the best preserved complex of mosaics from the early Komnenian period (ca. 1100) when an austere and hieratic manner typical for the Macedonian period and represented by the famous Christ Pantocrator image inside the dome, was metamorphosing into a more intimate and delicate style, of which The Angel before St Joachim — with its pastoral backdrop, harmonious gestures and pensive lyricism — is considered a superb example.