Route M61 operates between City QVB and Castle Hill via M2 Motorway and Baulkham Hills. It commenced operation on 20 December 2010.
The M61 originally operated through to Railway Square via George Street. Due to construction of the CSELR project, the route was truncated to City QVB from 4 October 2015.
Services on the Castle Hill to CBD corridor began in 1994, with the Route 610 “City Express” via Victoria Road during peak hours. This service was extended to full time operating and re-routed via the then brand new M2 Motorway in 1997. From 2010, all 610 services either became M61 or 610X services. In the 2013 “Sydney’s Bus Future” report, the M61 was designated as a rapid route, with priority to be given in terms of bus priority infrastructure and timetable upgrades.
The M61 operates between 5am and 11pm daily, with all night service on Friday and Saturday. It runs every 10 minutes during peak periods, 15 minutes during off-peak weekday periods, 20 minutes on weekends and hourly overnight The services are operated by CDC HillsBus from their Seven Hills depot using a mix of 14.5m single decker and 12.5m double decker buses.