thumb_20080918102239_roofs.jpg The urban landscape in Istanbul is constantly changing. In the Greek, Roman and Byzantine periods, the city was largely made up of the historic peninsula of Constantinople, with the citadel of Galata (also called Sykae or Pera, present-day Beyoğlu) at north, and Chrysopolis (Üsküdar) and Chalcedon (Kadıköy) at east, across the Bosphorus. These were all independent cities back then. The present City of Istanbul can be considered the metropolitan area of old Constantinople, encompassing every single settlement around the original city, and expanding even further with the establishment of new neighbourhoods and districts since the 19th century.