BOSPHORUS

The Bosphorus is the 32 km (20-mi)-long strait which joins the Sea of Marmara with the Black Sea, and separates the continents of Europe and Asia.

It's great for a half-day cruise north toward the Black Sea. You can return to Istanbul by land along the European shore and see all the sights.

The width of the Bosphorus varies from 500 meters (1640 feet) to 3 km (2 miles), its depth from 50 to 120 meters (164 to 394 feet), averaging about 60 meters (197 feet) deep.

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. (For self-guided touring, I've divided it into the Southern Bosphorus and Northern Bosphorus.)

Traditionally called Bogaziçi (boh-AHZ-ee-chee, "Within the Strait"), more recently it's been called the Istanbul Bogazi, Istanbul Strait, perhaps to differentiate it from the Dardanelles (Hellespont), called the Çanakkale Bogazi.

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."