Chinggis Khaan International Airport (CNG) is Mongolia's major international airport for all foreign visitors. Cheap flights to Mongolia are available during the winter and autumn. Flights to Mongolia are served by several different airlines including Aeroflot, Air China, and Korean-Air are operating flights connecting Ulaanbaatar with Moscow, Beijing, and Seoul. Flights are available all year round by Mongolian national carriers by MIAT Mongolian Airlines, Aero Mongolia, Hunnu Air, and Eznis Airways. There are two ways to visit Mongolia by train either China or Russia. Trans-Siberian Railway runs from Moscow to Vladivostok. The Trans-Mongolian Railway is connected to the Trans-Siberian by a branch line from Ulan-Ude, providing a link between the Trans-Siberian and the Chinese railway system.