Brussels-South railway station
Line 3 and Line 4 are tram lines using the North-South Axis tunnel which crosses the city center from Brussels-North railway station to Brussels-South railway station and Albert premetro station. Line 3 runs from Churchill in the south to Esplanade in the north. Line 4 runs from Brussels-North railway station to the Stalle car park in the south. This North-South axis is being upgraded to metro service: works have begun in 2019, including northeastward prolongation of the metro tunnel, and the transition to conventional metro is foreseen for 2024.