Üsküdar (Turkish pronunciation: [ysˈcydaɾ]) is a municipality and district of Istanbul Province, Turkey. Its area is 35 km, and its population is 524,452 (2022). It is a large and densely populated district on the Anatolian (Asian) shore of the Bosphorus. It is bordered to the north by Beykoz, to the east by Ümraniye, to the southeast by Ataşehir and to the south by Kadıköy; with Karaköy, Kabataş, Beşiktaş, and the historic Sarayburnu quarter of Fatih facing it on the opposite shore to the west. Üsküdar has been a conservative cultural center of the Anatolian side of Istanbul since Ottoman times with its landmark as well as numerous tiny mosques and dergahs.
Previously known as Chrysopolis and Scutari, present-day Üsküdar is a major transport hub, with ferries to Eminönü, Karaköy, Kabataş, Beşiktaş and some of the Bosphorus suburbs. Üsküdar is a stop on the Marmaray rail service at the point where it starts its journey under the Bosphorus, re-emerging on the European side at Sirkeci. Via Marmaray, Üsküdar is linked to Gebze on the Asian side of the city and Halkali on the European side. Üsküdar is also a stop on the M5 Metro line to Çekmeköy. Buses run along the Bosphorus shore all the way up north to Anadolu Kavağı in Beykoz district. A bus service also operates to the summer town of Şile on the Black Sea.