Екатеринбу́рг (Yekaterinburg or Ekaterinburg), is Russia's fourth-largest city after Moscow, St. Petersburg, and Novosibirsk, with a population of 1,349,772 as of 2010. Yekaterinburg is the administrative centre of Sverdlovsk Oblast located in the middle of the Eurasian continent, on the border of Europe and Asia. It is a major centre of industry. Situated on the Iset River, the city was built in 1723 and named by Emperor Peter the Great for his wife Empress Catherine. In 1924, the Soviet Union changed the city's name to Свердло́вск (Sverdlovsk) after Communist party official Yakov Sverdlov. The name Yekaterinburg was restored in 1991 when the Soviet system was abolished.