Hagia Irene (St. Irene), one of İstanbul’s most distinctive landmarks, is rarely open to the public but when it is, make the most of it. You’ll find this Byzantine church dating back to the 6th century and built during the reign of Justinian in the first courtyard of Topkapı Palace. Consisting of an atrium, a three-naved naos and an apse, it is typically Byzantine in its structure and materials; during this period, the emphasis was on a building’s interior, rather than exterior adornments.
Because of its proximity to Hagia Sophia (a perfect example of architecture of the period), it was not converted into a mosque after the Conquest in 1453, and has not undergone any major changes since.
In 1869, Hagia Irene was renamed the Müze-i Hümayûn (Imperial Musem), but because it eventually proved too small, the museum was moved in 1875 to the Çinili Köşk (Tiled Pavilion). After 1908, it was used as the Military Museum. Following its latest restoration, it was reopened to visitors, and now hosts many concerts and cultural events.