Aylesbury–Princes Risborough line
|Aylesbury–Princes Risborough line|
|Type||Rural branch line, Heavy rail|
South East England
|Number of tracks||1|
|Track gauge||1,435 mm (4 ft 8 1⁄2 in)|
|Old gauge||7 ft (2,134 mm)|
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 line was built as a single track broad gauge branch of the Wycombe Railway in 1863. The branch became part of the Great Western Railway when the latter took over the Wycombe Railway in 1867. The GWR converted the line to standard gauge in 1870. The branch was incorporated into the newly formed Great Western and Great Central Joint Railway in 1906. Network SouthEast made the branch part of its Chiltern subdivision in the 1980s.
Passenger services are now operated by Chiltern Railways. The line is regularly used by freight services operated by DB Cargo UK and Freightliner. The trains, referred to as "binliners", carry waste from London to a waste facility near the site of the former Great Central Railway station at Calvert. For this purpose, during Chiltern Railways' Evergreen 2 project the line was resignalled with two new signals at Little Kimble, one for each direction of travel. These allow two trains to travel in the same direction, thus allowing a passenger service to follow the freight train or vice versa.
The current timetable, produced for December 2016, allows for one passenger service per hour to operate along the line in each direction, with the vast majority of services operating directly to/from London Marylebone.  Peak time services in the evening and mornings do continue to use the British Rail Class 121 'Bubble Car' with services operating between Princes Risborough and Aylesbury. 
As such its 1tph service generally requires a change at Princes Risbrough or Aylesbury to access other parts of the network.
- Route plan 16: Chilterns (2009) Network Rail.
- "Download our timetable | Chiltern Railways". www.chilternrailways.co.uk. Retrieved 2016-12-11.
- Association of Train Operating Companies - official timetable