7 miles long and surrounded by moorland The Aylesbury–Princes Risborough line is a rural branch line between Princes Risborough and Aylesbury in Buckinghamshire, England. The line is single track throughout with a maximum speed of 40 mph. The rolling stock: The British Rail Class 121 or ‘Bubble Car’ is a single-car double-ended diesel multiple unit. 16 driving motor vehicles were built from 1960, numbered 55020–55035. These were supplemented by ten single-ended trailer vehicles, numbered 56280–56289 (later renumbered 54280–54289). They have a top speed of 70 mph, with slam-doors, and vacuum brakes. The driving motor vehicles were nicknamed "Bubble Cars" by some enthusiasts (a nickname endorsed and made official by final passenger service operator Chiltern Railways). The Class 121 is Britain's longest serving DMU, operating in passenger service for 57 years until 2017. these will run 35 services back and forth between Aylesbury To princes risborough scenarios: Holiday Traffic: Run a Holiday Special service from Aylesbury to Monks Risborough Only due to track maintenance First Train of the Day: drive the first train of the day from Princes Risborough to Aylesbury Last Train Of the Day: drive the last train of the day from Aylesbury to Princes Risborough Derailment Delays: run a service from Aylesbury to Little Kimble only after a freight train has derailed in the rain
