The Saint Petersburg Metro (Russian: Петербу́ргский метрополитен) is the underground railway system in Saint Petersburg and Leningrad Oblast, Russia. It has been open since November 15, 1955. Formerly known as the V.I. Lenin Order of Lenin Leningrad Metropoliten (Russian: Ленинградский Ордена Ленина Метрополитен имени В.И. Ленина), the system exhibits many typical Soviet designs and features exquisite decorations and artwork making it one of the most attractive and elegant metros in the world. Due to the city's unique geology, the Saint Petersburg Metro is one of the deepest subway systems in the world and the deepest by the average depth of all the stations. The system's deepest station, Admiralteyskaya, is 105 metres below ground. Serving two and a half million passengers daily, it is also the 12th busiest subway system in the world.