The following is a list of tram/streetcar (including heritage trams/heritage streetcars), or light rail systems with their track length, track gauge, electrification system.
The vast majority of tram systems use 1,435 mm (4 ft 8+1⁄2 in) standard gauge.
Metre gauge is mainly present in some old, continuously operating systems in Central Europe.
Some old systems upgraded to 750 V in recent years (mostly in Germany[1]) while some systems (e.g. Romania) downgraded the voltage to 600 V to use the second-hand vehicles coming from the upgraded German networks.
Very few vintage systems are horse-drawn tram or cable car.