With the resumption of services in 1955, all traffic on the line has been controlled from an office in Harbour station, known simply as "Control". With the exception of some early morning and late night movements by works trains, this office is manned constantly when passenger-carrying services are in operation. Its remit was expanded in 1997 with the commencement of public services on the Welsh Highland Railway between Caernarfon and Dinas and its subsequent expansion south towards Porthmadog. Additionally, for 2007 and 2008, when a connection was in use with the WHR(P), there was a requirement to coordinate with its operations on the new main line.