The premetro network consists of three tram lines (T3, T4, and T7) that partly travel over underground sections that were intended to be eventually converted into metro lines.
Premetro-netværket består af tre sporvognslinjer (T3, T4, and T7) som kører delvist gennem de undergrundsstrækninger, som det oprindeligt var meningen skulle konverteres til metrolinjer.