Daphnion or Daphni is a Byzantine monastery 11 km from the center of Athens, located in the Daphnian grove on the road to Eleusis. It was founded in the 6th century on the site of the pagan sanctuary of Daphne Apollo, which was ravaged by the Goths in 395. Part of the columns of the ancient temple went to the construction of the church, the rest were taken to England by Lord Elgin.

The monastic cross-domed temple belongs to the best surviving examples of architecture from the era of the Macedonian dynasty and the Middle Byzantine period as a whole. Its construction can be attributed to the first half of the 11th century. Mosaic decoration appeared somewhat later, at the turn of the 12th century.

In 1821, the monastery was closed, and in 1990 it was listed by UNESCO as a World Heritage Site as one of the most valuable surviving monuments of the Byzantine world.