Ashendon Junction

[2] It was a high-speed flying junction carrying southbound GWR trains from Birmingham via Bicester North (Engineer's Line Reference NAJ2) on an embankment with a girder bridge over the top of northbound Great Central trains travelling from London Marylebone on to the 90 mph five-mile link to Grendon Underwood Junction (Engineer's Line Reference GUA) where they rejoined the original Great Central Main Line towards Brackley and beyond to the East Midlands and North.

When the Great Central was closed south of Rugby in September 1966, the junction became redundant and the trackwork was later dismantled.

The link to Grendon Underwood was already relatively little used by then, at least as far as passenger trains were concerned, most services from Marylebone towards Brackley and beyond using the original GC route through Aylesbury after long-distance expresses were ended in 1960.

[3] Few signs of the old Great Central lines can now be seen from ground level on the site of the junction itself, but the trackbed is clearly visible from the air.

Little other evidence remains, except that over the best part of a mile the twin tracks of the Chiltern route still diverge at this point, a relic of the old layout preserved when Chiltern Railways redoubled the line between Princes Risborough and Aynho Junction in 1998, it having been singled in the late 1960s.