known in previous incarnations （作为化身、代表）as byzantium （拜占庭）and constantinople （君士坦丁堡）, the ancient city of istanbul has over the past few decades grown a healthy cosmopolitan skin. turkey had an economic good time in the 1980s that led in turn to resurgence （恢复生机）in national tourism when the thoroughfares of istanbul were with new restaurants, hotels, cafes and cultural institutions. the feel-good optimism was dashed by a devastating in 1999 but the city has since recovered some if its equanimity （心绪平静）.
the bosphorus, the flowing between the sea of marmara and the black sea, creates a natural north-south divide in istanbul - european istanbul comprises the bulk（大部分）of the city to the west, while asian istanbul is to the east. european istanbul is itself divided by the golden horn into the old city to the south, and beyoglu and other modern districts to the north.
the old city is where you'll find all the main sights, such as topkapi sarayi (topkapi palace), sultan ahmet camii (blue mosque), aya sofya (sancta sophia), the atmeydani (hippodrome) and the old city walls. the 21st-century of istanbul is a short walk north across the galata bridge, and is exemplified by bustling taksim square, the eye of the city's commercial storm. buses, trams and the developing metro system, not to mention footpower, will get you around the two main parts of the city - ferries（渡轮）can run you between them and across the bosphorus to asian istanbul, although there's little of interest for tourists in this area.