Yedikule Hisari or shortly Yedikule, being one of important architectural arts of Istanbul is on the south of city land water and under authority of Directorate of Hisarlar Museum in the same town.The land part of Hisar was built during reign of Theodosios II (408-450) as the most important entrance of the city walls and also an additional construction was made behind Porta Aurea having an important place in Byzantine history. 4 years after conquer of Istanbul, an inner castle was built by Sultan Mehmet II in 1457-1458. Thus Byzantine and Ottoman Period buildings combined.
The walls of Yedikulehisar are in shape of stars. There is one door on city side. No building was made adjacent to walls. There one dizdar (castle guard), dizdar assistant, 6 officer and 50 soldiers. There was a disdar's house and 12 guards' houses. Even the traces of shelters and store houses not reaching today can be seen at present. Only a minaret of the mescid remained until 1905 located in the centre of the courtyard and fountain in the front can be seen. The mescid had a quarter which was pictured in a picture of 17th century, and the time of destruction of the quarter is not known either.