GW.2FGC Joint Line Chiltern Main Line

robinson a5 steam locomotives operated gcr (later lner) local services high wycombe, princes risborough , aylesbury

the joint line ran northwest via gerrards cross high wycombe, met wycombe railway s single-track branch maidenhead aylesbury via princes risborough. north of high wycombe line followed, significant upgrading of formation, including dualling , new alignment line north of saunderton. original route, down line, has gradient of 1 in 88, steep heavy coal trains run gcr. result, 2 tracks horizontally , vertically separated, down line crossing chiltern hills @ risborough gap , line passing through 88-yard (80 m) tunnel on flatter gradient.

on reaching princes risborough, new construction started. station major junction, single-track line dividing 3 branches: chinnor , watlington (which survives in part chinnor , princes risborough railway); thame, wheatley , oxford; , aylesbury. joint line constructed in v formed 2 latter branches, , ran north west ashendon (not yet junction), line curved north join gcr s pre-1906 main line @ grendon underwood junction in buckinghamshire.

the joint line completed in 1906 (with portions opening earlier) gwr , benefited both parties. gcr, unable secure adequate access route via aylesbury, amersham , harrow, gained new , fast bypass route express passenger , freight trains between london , east midlands, while gwr gained faster route birmingham trains, paddington via gerrards cross , princes risborough , temporarily (1906–1910) on wycombe railway via thame regain original route @ oxford, pending opening of bicester cut-off banbury (see next subsection). gcr expresses non-stop between london , rugby use either metropolitan route or joint line, while joint line used gwr expresses paddington birmingham , wolverhampton , on shrewsbury , mid/north wales, chester , birkenhead.