Ghost slip is an informal term to describe a section of motorway which was designed to easily allow another exit or entry to be added. The idea is that by building the very first part of the slip road - often called a stub - the rest of it can be built at a later time without disturbing traffic.
In some places, especially around major junctions, ghost slips were provided to make space for another motorway or flyover which was planned at the time the road was built. Other than those examples, a ghost slip is normally evidence of an unbuilt service station.
Seeing as most of Britain's motorways were built in the 1970s, any ghost slips which haven't been used by now are unlikely to ever be used. There have been problems with them being wrongly used as parking places, so they are often blocked off. Many have been removed during roadworks.
Ghost slips shouldn't be confused with police patrol ramps, which are similar in appearance but involve a steep ramp, and have signs saying what they are for.
List of Ghost Slips
This section only lists ghost slips that were provided to connect to a service station which was never built. Each one has its story told in Unbuilt Services. Other ghost slips are not documented here.
- Chapeltown (M1; some now used)
- Clifton (M6)
- Hatfield (M18)
- Harborough Magna (M6)
- Hensall (M62)
- Kempshott (M3; some now removed)
- Long Whatton (M1)
- Meon (M27; an elaborate example, now mostly removed)
- Methley (M62)
- Moreton Valence (M5)
- Newland Common (M5; now removed)
- Pucklechurch (M4)
- Staverton (M5)
- Tibshelf (M1; now mostly removed)
- Trumps Green (M3; was used during construction)
- Wilcrick (M4; the only example outside England)
Works Unit Only
"Works Unit Only" is a term used to sign motorway exits that aren't suitable for general use. Normally, the "works unit" is a maintenance compound.
Maintenance compounds themselves don't have anything to do with ghost slips. However, many maintenance compounds are also examples of half-built service stations. To complete the list of half-built service stations, the following maintenance compounds were built on the site of a planned service area:
Services Which Started As Ghost Slips
There are only really three service areas which had their land reserved when the motorway was built, and were then built as expected at a later date. All three of these (Sandbach, Toddington and Northampton) started out as works units, so their slip roads have always been joined up.
There are many more service areas which opened a few years after the motorway was built, meaning there may have been some ghost slips for a few years, but they don't really count because the intention was always to build them as soon as possible, it's just that they were delayed. Examples of these include Killington Lake and Corley.