, formerly known as Petrograd
(Петроград) (1914–1924), then Leningrad
(Ленинград) (1924–1991), is a city on the Neva River, at the head of the Gulf of Finland on the Baltic Sea. It is Russia's second-largest city after Moscow. With a population of roughly 5.4 million inhabitants, it is the fourth-most populous city in Europe, the most-populous city on the Baltic Sea, as well as the northernmost metropolis in Europe and the world. As an important Russian port on the Baltic Sea, it is governed as a federal city.