M25 motorway and Thurrock off junction 31 (to the east of London). Cobham services opened on 13 September 2012. Originally, the M25 was unlit except for sections around Heathrow, major interchanges and Junctions 23–30. Originally, low pressure sodium (SOX) lighting was the most prominent technology used, but widening projects from the 1990s onwards have all used high-pressure sodium (SON) lighting and this has diminished the original installations. By 2014 only one significant stretch was still SOX-lit (Junction 25–26) and the units were removed the same year. The motorway passes through five counties. Junctions 1A–5 are in Kent, 6–14 are in Surrey, 15–16
London Borough of Croydon is linked into the national motorway network via the M23 and M25 orbital motorway. The M25 skirts the south of the borough, linking Croydon with other parts of London and the surrounding counties; the M23 branches from the M25 close to Coulsdon, linking the town with the south coast, Crawley, Reigate, and Gatwick Airport. The A23 connects the borough with the motorways. The A23 is the major trunk road through Croydon, linking it with central London, East Sussex, Horsham, and Littlehaven. The old London to Brighton road, passes through the west of the borough on Purley Way, bypassing the commercial