Several countries that are landlocked and have no borders with the high seas retain their navies. Maybe it looks strange, why did they create a navy, even though there is no access to the open seas such as Indonesia, Australia and others. But as you look further, that even though they are landlocked, they have lakes and rivers that form the borders of the country. That’s where they exist and defend their country. This is no longer strange but something that is natural and necessary.
For example, Kazakhstan, Azerbaijan and Turkmenistan. All three are countries bordering the mainland with other countries. But all these countries have their navies. They maintain their naval fleet in the great lake, the Caspian Sea which forms the border of the country.
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In addition, there are other countries bordering on land such as Paraguay. The country has patrols on the main rivers because enemy nations can reach the heart of the Paraguay state via these rivers. Also, Switzerland is the most armed country out there, they have many patrol boats standing guard on many lakes. Even Hungary is a country which has many ships including minesweepers and warships. These countries all have their right and good reasons for defending their inland waters. However, this is different from Mongolia.
Mongolia is renowned as the most remote landlocked country after the Kazakh state. Its border is 600 km from the nearest coastline. Do you still think that Mongolia should have a navy, even though this is a country that is 600 km from the nearest coastline.

Mongolia’s only international border is the 10 km long Zigzag at the eastern end of Lake Uvs. Where a fraction is across Russia. So if Mongolians want to defend these waters, this is a legal thing for them. However, it seems that they are not really defending the country from this part of the water. Because realistically, Russia’s potential to invade Mongolia via this route is very small. Instead, the Mongolian navy maintains its navy in other waters: Lake Khövsgöl, which is entirely on land. Meanwhile, the Russian border is more than 13 km from the lake shore and is separated by high mountains.
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Why did Mongolia take the navy, this is inseparable from past history. It is the result of the country’s futile efforts to preserve its lost legacy. About 800 years ago, the Mongol state was ruled by Kublai Khan, this was the largest navy in the world. Reach the coverage area is covering
Central Asia, eastern Europe, with its maritime fleet along the China, Japan, Persian Gulf and Arabian seas.
Genghis Khan as the ruling king at that time led more than 4,000 ships to attack Japan. However, the invasion fleet was crushed by a violent hurricane. Where when the Japanese called it the divine wind (kamikaze). Later in its history, there have been thousands of Japanese pilots crashing their planes into enemy ships in suicide attacks in World War II. That goal is to defend Japan from its enemies.

But then at the end of the 13th century, the Mongol empire split into several kingdoms that stood independently. Subsequently, China conquered Mongolia and this caused the country of Mongolia to continue to be pushed further away from the coast and to become the most landlocked country today.