01 ) RUMELİ FORTRESS ( RUMELİ HİSARI )
This castle , built by Fatih Sultan Mehmet in 1452,has a 250 m.s long wall in south-north direction along the coast. The width of its bailey, in east west direction , is 125 m.s at most. With its seventeen towers this castle has played an important role in the Ottomans history both before and after the conquest of Constantinople . This castle which has been used as a prison in the XVIIIth and XIXth centuries, serves today as an open air theatre.
02 ) ANATOLIAN FORTRESS ( ANADOLU HİSARI )
Built by Yıldırım Beyazıt in 1399 , the castle stands on a rocky site , 2-3 m. above the sea level. It has a barley of 20 m.s diameter and is encircled by walls having a thickness of 1,5 m.s and a height of approximately 7 m.s There are , round and angular , six semitowers along the walls . An enormous tower of 25 m.s stands in the midst of the front wall.
01 ) GALATA TOWER ( GALATA KULESİ )
It was erected by the Genoese commercants against the Byzantines in 14th century. This tower , has a height of 64 m., has later been used as a fire tower is a night club today.
02 ) LEANDERS TOWER ( KIZ KULESİ )
This historical tower which stands on a huge mass of rock at the entrance of Bosphorus , close to Üsküdar was first built in the XII. Century by the Byzantian emperor Mannel Comnennos,than took today's form in Ottoman time . Today , it is still used as a lighthouse.