the gråkallen line () is an suburban tram line located in trondheim, norway. as the only remaining part of the trondheim tramway, it runs from the city centre at st. olav's gate, via the suburban area byåsen to lian. it is designated line 1, and is served by six class 8 articulated trams. after the closure of the arkhangelsk tramway in 2004, it became the world's northernmost tramway system.