Colas Alterra Zrt. is remodelling the tramway tunnel located at the right bank bridgehead of Budapest’s Chain Bridge. Essentially, the job covers the partial conversion of the existing tunnel, while other segments of the structure are dismantled and re-built. The assignment also includes the upgrade of the tram tracks, the direct current network and other related infrastructures. The goal of the project is to increase tramway curve radiuses and expand the interior dimensions of the tunnel, as the current clearance is insufficient for the CAF trams recently purchased by the city.