Since 2021, Turkey has launched the Istanbul Canal project with a high profile, carving a passage parallel to the Bosphorus on the west side of Istanbul, connecting the Mediterranean and Black Seas. Although Turkey claims that it is a project for the benefit of the world, it has raised concerns that the Bosphorus is a freely navigable waterway, while the completed Istanbul Canal will be charged.
The Turkish Strait is the only waterway connecting the Black Sea and the Mediterranean Sea, consisting of the Bosphorus, the Sea of Marmara and the Dardanelles. This section of the strait not only guards the sea route in the east-west direction, but also the meeting point of Asia Minor and the Balkan Peninsula in the north-south direction.
As the only country in the region that straddles two continents, it stands to reason that Turkey can divide the Turkish Strait as an inland sea, and with such a busy shipping route, the "toll" must be very considerable. However, under the intervention of European powers such as Britain, France, and the Soviet Union, the huge Ottoman Empire collapsed, and the 1936 Montreux Convention stipulated that merchant ships of various countries could pass freely at any time, and warships of countries bordering the Black Sea could pass freely in peacetime. Turkey has made little profit over the past few decades, but merchant ships from all over the world have been able to travel unimpeded between the Mediterranean and Black Seas. Sitting on the huge revenue that the Suez Canal and the Panama Canal bring to Egypt and Panama every year, Turkey, which guards important shipping lanes but has little benefit, naturally cannot remain indifferent.
As one of the busiest shipping lanes in the world, the Bosphorus is as congested as cars on the road. At present, Turkey is responsible for maintenance and management, and after the completion of the Istanbul Canal, will Turkey take the opportunity to increase the difficulty of passage through the Bosphorus? Who can guarantee that the Bosphorus will not gradually silt out due to disrepair? With the wisdom of the Turks, the old strait may silt up faster than the average person thinks. Not only are countries bordering the Mediterranean and Black Seas anxious, but even countries that have long relied on routes from East Asia to Europe are worried about what Turkey will do if the Istanbul Canal is built.
Generally, freighters from East Asia to Europe pass through the South China Sea, cross the Strait of Malacca into the Indian Ocean, and then sail into the Mediterranean Sea via the Suez Canal. The merchant ship then had two options, either to go west through the Strait of Gibraltar into the Atlantic Ocean, and then go all the way north to the countries of Western Europe; Either east across the Bosphorus into the Black Sea, and then upstream from the mouth of the Danube between Ukraine and Romania.
Figure - Balkan Canal Vision
The two routes have their own advantages and disadvantages, if you are going to Central and Eastern European countries, entering the Danube through the Black Sea is a good choice, the Bosphorus is free to navigate, and the route is much more convenient than the Atlantic Ocean.
The Danube is the second largest river in Europe after the Volga, with a total length of 2,857 kilometers, passing through ten Central and Eastern European countries such as Germany, Austria and Slovakia along the way, and freight is very convenient. In addition, in 1992 Germany connected the Danube with the Rhine, one of the busiest rivers in Europe, flowing through Austria, Germany and France before finally emptying into the North Sea in the Netherlands. The connection of the two large rivers allows the Black Sea to be directly connected to the North Sea, and after entering the Black Sea, cargo ships from Shanghai can go directly to the Dutch port of Rotterdam.
Figure - Danube
At present, this route is a bit of a detour for some countries, and the Balkan countries represented by Serbia and Greece have come up with the idea of opening a new canal in the Balkans to bypass the Istanbul Canal and the Bosphorus. This Balkan canal is equivalent to cutting the entire Balkan Peninsula, connecting the Aegean Sea with the Danube, that is, from the coastal city of Thessaloniki in Greece to the north, through North Macedonia, connecting the Danube in Serbia.
The north-south canal looks long, but the section of the river that really needs to be excavated is not long, and most of the work is dredging and widening on the original channel. Thessaloniki is the mouth of the Vardar River in the Aegean Sea, which originates in North Macedonia, and there is a tributary of the Danube called the "Morava" to the north of this river, so in theory, as long as the Vardar River and the Morava River are connected, the Aegean Sea and the Danube can be connected. Merchant ships entering the Mediterranean via the Suez Canal will not have to detour the Istanbul Canal or the Bosphorus, but will sail directly into the Danube from the Aegean Sea.
The idea of a Balkan canal was raised more than a hundred years ago, but it was not urgent. The Istanbul Canal and the Bosphorus are separated on both sides of Istanbul, the difference is only that the canal charges and the strait is free. If Turkey sits on the ground by then, I believe that the Balkan Canal will not be long before it comes out, and only the canal can defeat it.