Turkey is a country that straddles two continents, Asia and Europe, with a total area of about 783,600 square kilometers, 97% of the territory is located in Asia, and 3% of the territory is located in Europe. Bordered by the Black Sea to the north and the Eastern Mediterranean to the south, Turkey has a long coastline of 7,200 km.
Between the two parts of Turkey's territory in Asia and Europe, Turkey's inland sea is the Sea of Marmara. However, foreign merchant ships can also move freely in Turkey's inland seas, which makes Turkey very helpless. So what's going on?
First, Turkey's inland sea. The Sea of Marmara covers an area of about 11,350 square kilometers and is surrounded by Turkey's territory, with the Asia Minor Peninsula to the east and the Balkan Peninsula to the west.
The Sea of Marmara is connected to the Black Sea by the Bosphorus to the north and the Aegean Sea to the south by the Dardanelles and is an integral part of the Straits of Turkey.
The Bosphorus is about 31.5 kilometers long and 737 meters to 3.7 kilometers wide. The Dardanelles Strait is about 64 kilometers long and 1.7 to 7.5 kilometers wide. Turkey's territorial waters are 6 nautical miles wide, equivalent to about 11.1 kilometers, and the two outlets to the Sea of Marmara, the Dardanelles and the Bosphorus, are both less than 22.2 kilometers wide.
There are many islands and reefs in the Sea of Marmara, the largest of which is Marmara Island, with an area of about 117 square kilometers. The width between islands and reefs and from reefs to the coast is also less than 22.2 kilometers, and the Sea of Marmara belongs to Turkey's internal sea by the standards of the United Nations Convention on the Law of the Sea.
The coastal State has complete and exclusive sovereignty over the inland seas owned by a State, and the coastal State has the right to prohibit any foreign ship from entering its own internal seas. However Turkey exceptions, Turkey did not have the right to prohibit any foreign merchant ship from sailing into its own inland sea, the Sea of Marmara.
Second, the strategic value is too great. Turkey is a country of great strategic value, and on land, Asia Minor has been a land route between Asia and Europe since ancient times. Historically, the Roman Empire, Alexander's Empire, entered Asia through Asia Minor. The Ottoman Empire also used Asia Minor as a springboard to conquer Constantinople, the capital of the Byzantine Empire.
On the ocean, Turkey holds the Turk Strait, an important shipping route connecting the Black Sea and the Eastern Mediterranean. The Black Sea coast is dotted with Russia, Ukraine, Romania, Bulgaria and other countries, and ships from these countries need to pass through the Turk Strait to enter the Eastern Mediterranean.
The Sea of Marmara is an important part of the Straits of Turkey, and according to statistics, the total tonnage of ships passing through the Sea of Marmara reaches 400 million tons per year.
Third, the intervention of major powers. Turkey connects Asia and Europe, connecting the Black Sea and the Eastern Mediterranean, and is known as the crossroads of Asia and Europe. Due to the importance of value, the world powers do not allow Turkey to fully control the Turkey Strait. The Straits of Turkey, including the Sea of Marmara, have always been the focus of contention between Russia and the West.
As early as the 18th century, Tsarist Russia forced the Ottoman Empire to sign the Peace of Chukuk-Kenargi, and Russian merchant ships were granted free passage through the Turkey Strait. In 1833, Tsarist Russia forced the Ottoman Empire to sign the Treaty of Vinkar-Iskelesi, and Russian military ships were granted free passage through the Turkey Strait.
Tsarist Russia's privileges in the Turkey Strait are getting bigger and bigger, and there are even plans to seize Istanbul and completely control the Turkey Strait, which is difficult for Western powers to accept. After the outbreak of the Crimean War, Tsarist Russia was defeated and forced to sign the London Treaty, which stipulated that Turkey had the right to prohibit Russian military ships from passing through the Turkey Straits, and merchant ships could still pass freely.
In 1936, Britain, France, the United States, the Soviet Union and other major powers held a conference in Montreux, Switzerland, to discuss the passage of the Turkey Strait. At the meeting, Turkey said that the Sea of Marmara is Turkey's internal sea and that Turkey should have the right to prohibit any foreign ships from entering its own inland sea. Turkey's claims were ignored by other countries, and the conference eventually resulted in the Montreux Convention, which stipulates that merchant ships from all over the world can freely navigate through the Turkey Strait, including the Sea of Marmara. However, there are restrictions on warships, and the convention stipulates that warships of the Soviet Union and other Black Sea countries can freely pass through the Turkey Strait in peacetime, and that the passage of warships of other countries requires Turkey's permission. In times of war, Turkey has the right to prohibit the passage of warships of any country through the Turkey Straits.
The Montreux Convention is an international convention on the Straits of Turkey and is not affected by the United Nations Convention on the Law of the Sea. Therefore, according to this international convention, merchant ships from all over the world can freely navigate the Sea of Marmara in Turkey's inland sea.