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
Central line (London Underground) underground railway to have the station platforms illuminated electrically. All the platforms were lit by Crompton automatic electric arc lamps, and other station areas by incandescent lamps. Both the City and South London Railway and the Waterloo and City Railway were lit by gas lamps, primarily because the power stations for these lines were designed with no spare capacity to power electric lighting. With the white glazed tiling, all underground Central London Railway platforms were very brightly lit. The use of electric lighting was further made possible because the Central London was also the first tube railway to use AC