Exedra, Church of St. Irene, Istanbul, rebuilt by Justinian in the mid-6th century and again after 740.

Within the first courtyard stands the church of Haghia Eirene, one of Istanbul's most ancient churches and the only Byzantine church in Istanbul with its atrium intact It was not converted into a mosque after the conquest but used as an armory by the janissaries. Subsequently it became a military museum and is now a venue for classical concerts.A narrow lane leading down the hill from the church takes you to Gülhane Park which was once part of the palace gardens. Halfway down the hills is the Tiled Pavilion and the Archaeological Museum, possessing one of the most outstanding collections in the world.