Road: M25 at J5
(also accessible to traffic on the A21 and the B2211)
Location: Chevening, Sevenoaks, Kent
Other names: Sevenoaks, Chevening
Date planned: 1970-1976
Grid reference: TQ497567
See also: Gatton Bottom, Pedham Place
Chevening services (later called Sevenoaks) would have been built at what is today J5 of the M25, Chevening Interchange.
Originally the junction would have been a roundabout, with the M25 running underneath and the A21 running above. An assessment of the options for building services in this area concluded Chevening would be the best option because the building of the motorway would have already harmed the environment.
The interchange would have included a service station in the south-eastern quadrant, located on open land north of Chipstead. The services may well have backed on to a nearby lake, and they would have included public access to Chipstead Road in a similar fashion to that of South Mimms, another service area on the M25 located off exactly the same design of junction.
Chevening was also important because it was the point from which all M25 services were measured, working clockwise.
Generally, building services at junctions was discouraged, but in this case the engineering was not considered to be too difficult. It was expected to open in 1976.
There are two arguments as to why the design of the Chevening Interchange had to be changed. One is that the roundabout would have crossed the Chevening Estate, and the sale of land there required the Prime Minister's approval. The plot of land available was quite small too.
The second is that when the route of M25 was changed to head north from here, the traffic flows had to be re-analysed. In 1976 it was confirmed a roundabout would not be possible, so the services couldn't be incorporated.
The truth is probably the first caused them to look elsewhere, and the second confirmed it. Fortunately there was a a fall-back option: Titsey Woods had already been identified in case Sevenoaks was unavailable, and after a long legal process this was eventually built.