Saint Petersburg saw the arrival of street rail transport during the 1860s in form of horse-drawn rail carriages. The first, freight-only street railway track was opened in 1854 to serve one of the industrial city suburbs. In 1863, three passenger lines in the city centre came into operation. Several private companies were formed, and the horsecar network eventually expanded to 25 routes covering over 100 kilometres of track. Carrying over two million passengers a year, the street rail network in Saint Petersburg proved a successful commercial venture.