St. Petersburg, Russian Sankt-Peterburg, formerly (1914–24) Petrograd and (1924–91) Leningrad, city and port, extreme northwestern Russia. A major historical and cultural centre and an important port, St. Petersburg lies about 400 miles (640 km) northwest of Moscow and only about 7° south of the Arctic Circle. It is the second largest city of Russia and one of the world’s major cities. St. Petersburg has played a vital role in Russian history since its founding in 1703. For two centuries (1712–1918) it was the capital of the Russian Empire. The city is remembered as the scene of the February (March, New