Bosporus Strait

thumb|Location of the Bosporus (red) relative to the Dardanelles (yellow) and the [[Sea of Marmara]] thumb|Close-up satellite image of the Bosporus Strait, taken from the International Space Station in April 2004. The body of water at the top is the [[Black Sea, the one at the bottom is the Marmara Sea, and the Bosporus is the winding waterway that connects the two. The western banks of the Bosporus constitute the geographic starting point of the European continent, while the banks to the east are the geographic beginnings of the continent of Asia. The city of Istanbul is visible along both banks.]] thumb|Aerial view of the Bosporus taken from its northern end near the Black Sea (bottom), looking south (top) toward the Marmara Sea, with the city center of Istanbul visible along the strait's hilly banks

The Bosporus or Bosphorus Strait is a natural strait and an internationally significant waterway located in Turkey which is straddled by the city of Istanbul. The Bosporus connects the Black Sea to the Sea of Marmara and forms one of the continental boundaries between Asia and Europe. It also divides Turkey by separating Asia Minor from Thrace. It is the world's narrowest strait used for international navigation.