Explore BOSPHORUS by public ferry in Istanbul

The Bosphorus is the 32 km (20-mile)-long strait which joins the Sea of Marmara with the Black Sea in Istanbul, and separates the continents of Europe and Asia. It runs right through the heart of Istanbul, past the Istanbul Modern Art Museum, several Ottoman palaces, at least two fortresses, forested hills, and shore villages with Ottoman architecture.
Its English name comes from a Greek legend: Zeus had an affair with a beautiful women named Io. When Hera, his wife, discovered his infidelity, she turned Io into a cow and created a horsefly to sting her on the rump. Io jumped clear across the strait. Thus bous = cow, and poros = crossing-place: Bosphorus = 'crossing-place of the cow.'
Today, the way to enjoy the Bosphorus is to take a cruise by traditional ferry, TurYol boat or Dentur Avrasya boat, a self-guided tour of the European shore, or to relax at a tea-house or restaurant along its shores.
Source: turkeytravelplanner.com