The Copenhagen Metro expanded radically with the opening of the City Circle Line (M3) on September 29, 2019. The new line connects all inner boroughs of the city by metro, including the Central Station, and opens up 17 new stations for Copenhageners. On March 28, 2020, the Nordhavn extension of the Harbour Line (M4) opened. Running from Copenhagen Central Station, the new extension is a branch line of M3 Cityring to Osterport. The M4 Sydhavn branch is expected to open in 2024. The new metro lines are part of the city's strategy to transform mobility towards sustainable modes of transport such as public transport and cycling as opposed to automobility.