This document provides a guide to the city of Istanbul, Turkey. It begins with a brief history of Istanbul, noting its origins as Byzantium and Constantinople before becoming Istanbul under Ottoman rule. It then outlines Istanbul's main neighborhoods and districts, both on the European and Asian sides of the city. Finally, it highlights some of the top sights to see in Istanbul, including Aya Sofya, Topkapi Palace, the Blue Mosque, and the Grand Bazaar. The guide provides context and basic visitor information about each of these major attractions in Istanbul's old city center.