The branch forms a trailing connection with the main line immediately West of the platforms at Barnham railway station and then proceeds in a broadly southwards direction for 3.5 miles to Bognor Regis, where all trains terminate.
From that time onwards there were plans for a branch to Bognor, to provide a more convenient rail connection to the town.
After many failed proposals the Bognor branch was finally opened on 1 June 1864,[1] along with a new station at the junction, named Barnham.
As part of the conversion to double track, the opportunity was taken to re-organise the main line connection at Barnham, to allow through running onto the branch from the London direction, which until that time had not been possible.
The standard Southern electric traction system using 750 V DC current was installed, power being drawn from a "third" rail alongside the running line.