Palace of the Porphyrogenitus

The Palace of the Porphyrogenitus (Greek: το παλάτι τοῦ Πορφυρογεννήτου), known in Turkish as the Tekfur Sarayı ("Palace of the Sovereign"), is a late 13th-century Byzantine palace in the north-western part of the old city of Constantinople (present-day Istanbul, Turkey). An annex of the greater palace complex of Blachernae, it is the best preserved of the three Byzantine palaces to survive in the city (together with the ruins of the Boukoleon Palace; and the ruins of the Great Palace of Constantinople with its surviving substructures, retrieved mosaics and standing Magnaura section), and one of the few relatively intact examples of late Byzantine secular architecture in the world.

The Palace was constructed during the late 13th or early 14th centuries as part of the Blachernae palace complex, where the Theodosian Walls join with the later walls of the suburb of Blachernae. Although the palace appears at first glance to be named after the 10th-century emperor Constantine VII Porphyrogenitus, it was built long after his time, and is in fact named after Constantine Palaiologos, a son of the Emperor Michael VIII Palaiologos. "Porphyrogenitus", meaning literally "born to the purple", indicated a child born to a reigning emperor. The palace served as an imperial residence during the final years of the Byzantine Empire.

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