Volgograd stretches 80 km along the Volga, making it one of the longest cities in Russia. The tram network — partly underground in the centre, functioning as a de facto metro — is the main way to travel between the city's widely spaced districts. Tram 2 connects the central embankment with Mamayev Kurgan and is the route most visitors use. Trolleybuses and buses cover the gaps. Marshrutki (shared minibus taxis) run fixed routes and are hailed from the street. Public transport fares are very low.