Caspian Sea.
Poland borders both Germany and Russia and is located on the Baltic Sea, however the federal subject that borders Poland is separated from the main body of Russia and its other federal subjects.
China is the only country that borders both Russia and India.
The only country which borders both Russia and India is China.
The Mediterranean sea
The Baltic Sea borders both St. Petersburg and Kaliningrad. St. Petersburg is located on the eastern shore of the Baltic Sea in Russia, while Kaliningrad, an exclave of Russia, lies on the southern shore of the Baltic Sea. This strategic body of water connects various countries around the region.
Russia
The South China Sea
Alaska borders both Canada and Russia.
Both the Caribbean Sea and Gulf of Mexico.
There rea no countries which border both Russia and Switzerland.
Russia.
Both the Gulf of Mexico and the Caribbean Sea qualify as such.