I have suggested the Manchester Victoria to Bury route using the old class 504's before with a possible extension to Ramsbottom and Rawtenstall with DMU depending on the time frame. A good idea would also be the original Metrolink route when it first fully opened before the extensions. Bury to Altrincham/Bury to Piccadilly/Piccadilly to Altrincham. Two old heavy rail routes linked by the Manchester City centre lines. Trams would depart Bury every 6 minutes alternating between direct services to Altrincham and services to Piccadilly. Altrincham every 6 minutes to Bury and Piccadilly alternately. The longest service is Bury to Altrincham at around 50 minutes.
