TheTurkish Straits (Turkish:Türk Boğazları) are two internationally significant waterways in northwesternTurkey. The Straits create a series of international passages that connect theAegean andMediterranean seas to theBlack Sea. They consist of theDardanelles and theBosphorus. The straits are on opposite ends of theSea of Marmara. The straits and the Sea of Marmara are part of the sovereign sea territory of Turkey and are treated as Turkish internal waters.
Located in the western part of the landmass ofEurasia, the Straits are conventionally considered the boundary between the continents ofEurope andAsia, as well as the dividing line betweenEuropean Turkey andAsian Turkey. Owing to their strategic importance in international commerce, politics, and warfare, the Straits have played a significant role in European and world history. Since 1936, they have been governed in accordance with theMontreux Convention.
Asmaritimewaterways, the Turkish Straits connect various seas along theEastern Mediterranean, theBalkans, theNear East, andWestern Eurasia. Specifically, the Straits allows maritime connections from theBlack Sea all the way to theAegean andMediterranean Seas, the Atlantic Ocean viaGibraltar, and the Indian Ocean through theSuez Canal, making them crucial international waterways, in particular for the passage of goods coming in from Russia.
The Turkish Straits are made up of the following waterways;
Developments of economic activities threaten marine ecosystems including endemic dolphins andharbour porpoises.[2]
The Straits have had major maritime strategic importance since at least theMycenaean period, and the narrow crossings between Asia and Europe have provided migration and invasion routes (for Persians,Galatians, and Turks, for example) for even longer. In the declining days of theOttoman Empire, the "Straits Question" involved the diplomats of Europe and the Ottomans.
By the terms of theLondon Straits Convention concluded on 13 July 1841 between theGreat Powers of Europe — Russia, theUnited Kingdom,France,Austria andPrussia — the "ancient rule" of theOttoman Empire was re-established by closing the Turkish straits to allwarships whatsoever, barring those of theOttoman Sultan's allies during wartime.[4] This treaty became one in a series dealing with access to the Bosphorus, the Sea of Marmara, and the Dardanelles. It evolved from the secret 1833Treaty of Hünkâr İskelesi (Unkiar Skelessi), in which the Ottoman Empire guaranteed exclusive use of the Straits to "Black Sea Powers" (i.e., Ottoman Empire and Russian Empire) warships in the case of a general war.
The Straits became especially important in the course ofWorld War I (1914–1918) as a potential link between theEntente powers'Eastern andWestern Fronts. Anglo-French naval forcesfailed to take control of the Dardanelles (February – March 1915), but in the secretStraits Agreement diplomacy of March – April 1915, the members of theTriple Entente agreed — in the event of victory inWorld War I — to cede Ottoman territory controlling and overlooking the Straits to the Russian Empire. Anglo-French troops then launched theGallipoli campaign, an ultimately unsuccessful operation to take control of the Straits following amphibious landings on theGallipoli Peninsula (April 1915 to January 1916). Therevolutions inPetrograd in 1917 ultimately stalled Russia's own plans to seize the Straits.[5][6] On the Eastern Front , there were theBlack Sea raid, Cape Sarych,10 May 1915,Kirpen,8 January 1916.
The modern treaty controlling access is the 1936Montreux Convention Regarding the Regime of the Straits, which remains in force as of 2025.[update] This Convention mandates that Republic of Turkey allow the free passage of all civilian vessels in peacetime, and requires Turkey to allow warships of some nations to traverse the straits in peacetime, but only under strict conditions – restrictions on number, size, length of stay if entering theBlack Sea (if not a Black Sea power), advance notification to Turkey, and other conditions.
Saz[o]nov made plans for a seizure of the Turkish straits.
Sazonov, Sukhomlinov, and Grigorevich had drawn up a detailed plan for readying Russia to seize Constantinople and the Ottoman Straits in case of war. The plan covered [...] the acceleration of the mobilisation timetable, which would see the first day troops could be put ashore at the Bosporus speeded up from Mobilisation Day (M) + 10 to M + 5 [...]. [...] After learning the news from Sarajevo, Sazonov [...] wanted to know whether, in accordance with measures ordered in February [1914], the first Russian troops would now be able to land in the Bosphorus within 'four or five days' of mobilisation. [...] Sazonov was preparing for a European war, in which Russia's key strategic objective was to seize Constantinople and the Straits.
40°43′21″N28°13′30″E / 40.7225°N 28.2250°E /40.7225; 28.2250