When the final plan for the M25 was announced, there was to be four services: the three that are already built and one at Iver, just north of the M4 junction.
The original plans were discussed at a public inquiry and would have been connected to Iver railway station to create a park and ride site. This never materialised, and in 1998 the services were the subject of another public inquiry.
It should be noted that had the services gone ahead they would have been very close to the M4 junction. It looks like the reason why the plans were dropped the first time was that plans to widen the M25 took over and would have got in the way of any plans for services here.
Services have previously been considered to the south of the M4 as far back as 1983, but they were ruled out to keep the site clear for the Heathrow Terminal 5 junction.
- CBRD - Opening Booklets - a series of motorway opening booklets, including one for the M25 that deals with service areas.