Where empires collide: Setting off on a voyage from Istanbul

A journey on the Black Sea begins in Istanbul, a place where empires and cultures collide. The Bosphorus strait is as busy a waterway now as it was in ancient Greek, Byzantine or Ottoman times. Presenter Tim Whewell takes his place on a ferry on the first step of a voyage on the Black Sea - a region of great strategic importance where Russia meets Turkey.

Image: Istanbul panorama Credit: Tony Jolliffe/BBC