Tyler Hicks/The New York Times FROM a skyline featuring both minarets and church spires to the call to prayer competing with lounge music in a hip cafe, Istanbul is the only major city to span two continents. While it is known for sights dating back thousands of years, it also has a fascinating, and often ignored, contemporary scene that is finally receiving international attention. As a 2010 European Capital of Culture, the city is showcasing local artists in both historic areas and new museums — yet another example of how Istanbul is among the world’s most visually stimulating cities. Read