Arun is a local government district in West Sussex, England. It contains the towns of Arundel, Bognor Regis and Littlehampton, and takes its name from the River Arun, which runs through the centre of the district
Arun was formed on 1 April 1974, under the Local Government Act 1972, merging the Urban Districts of Bognor Regis and Littlehampton, the municipal borough of Arundel and parts of Chichester and Worthing Rural Districts.