The new North Station "Superstation" opened in 2004 and serves both the Green and Orange Lines. The upper level of the station has the ticket concourse and the northbound Green Line platform. The lower level has the soutbound Green Line platform and both Orange Line platforms, with the southbound OL and GL tracks on either side of the same platform. GL trains that terminate here continue to a small 2-track underground yard squeezed between the tracks to/from Lechmere, where they change ends and head back to the southbound platform in North Station. The tracks to Lechmere curve around at the end of the yard and head up a new incline to Science Park.