Lisbon Tram
The first tramway in Lisbon entered service on 17 November 1873, as a horsecar line. On 30 August 1901, Lisbon's first electric tramway commenced operations. Within a year, all of the city's tramways had been converted to electric traction. Until 1959, the network of lines continued to be developed, and in that year it reached its greatest extent. At that time, there were 27 tram lines in Lisbon, of which six operated as circle lines. As the circle lines operated in both clockwise and anticlockwise directions, each with its own route number, it is more correct to speak of a total of 24 tram routes, all of them running on 900 mm (2 ft 11 7⁄16 in) narrow gauge tram lines.