Russia, the largest country in the world, occupies one-tenth of all the land on Earth. It spans 11 time zones across two continents (Europe and Asia) and has coasts on three oceans (the Atlantic, Pacific, and Arctic). Russia has about 100,000 rivers, including some of the longest and most powerful in the world. It also has many lakes, including Europe's two largest: Ladoga and Onega. Lake Baikal in Siberia contains more water than any other lake on Earth. Russia borders 14 countries, Azerbaijan, Belarus, China, Estonia, Finland, Georgia, Kazakhstan, North Korea, Latvia, Lithuania, Mongolia, Norway, Poland, and Ukraine. It shares maritime borders with Japan, Sweden, Turkey, and the United States.