With its strate­gic loca­tion on the Bospho­rus penin­su­la between the Balka­ns and Ana­to­lia, the Black Sea and the Mediter­ranean, Istan­bul has been asso­ci­at­ed with major polit­i­cal, reli­gious and artis­tic events for more than 2,000 years. Its mas­ter­pieces include the ancient Hip­po­drome of Con­stan­tine, the 6th-cen­­tu­ry Hagia Sophia and the 16th-cen­­tu­ry Suley­maniye Mosque, all now under threat from pop­u­la­tion pres­sure, indus­tri­al pol­lu­tion and uncon­trolled urban­iza­tion.