Population (people): 1,372,565
Number of stations: 163
Length (km): 123.7
Riders per annum: 412,583,000

The first tunnel within the Stockholm metro was inaugurated for subway traffic on October 1, 1950. As of today, the metro system involves 100 stations, linked by 3 lines which makes the Stockholm metro one of the largest subway systems in proportion to population of the city it serves, in the world, with an annual ridership of 328 million. The Metro is undergoing an expansion and will add another line which is projected to be in use in 2020. The metro is owned by the Stockholm County Council although its operation is contracted to the Hong Kong based company MTR Corporation.