What is a service area?
This website writes a lot about service areas, but what actually is one? If you over-think it, it can get a little complicated.
Highways England has their own definition for what they consider to be qualifying motorway service areas and other service areas. Once a place qualifies, it can receive signposts, and only then can it be considered official.
However, the phrases "service area", "service station" and "services" are often used colloquially, with a more vague meaning. According to the Cambridge Dictionary, a service area is:
...and they say the phrase can be used interchangeably with "services" or, when used in Britain, "service station". In other localities a service station may be a place that sells fuel only, and confusingly that second meaning is used in Britain too.
This would make sense, and it would reflect how most people see it. A place can meet all those expectations without completing the government's requirements, and therefore be considered by most people to be an unofficial service area.
It also underlines one key point: a petrol station is only one part of a service area. Once it gains other facilities, it becomes a service area. A motorway resting area that meets certain criteria but not all will be classed as a rest area, while the same on an A-road would merely be a lay-by.
The history of these terms, especially the linguistically confusing word "services", is quite odd. The dictionary claims that "services" is a plural, even though it describes a single place, a bit like how a "group of mountains" may be describing a single place.
In the early days of the motoring era, it was common for places that sold fuel to also perform vehicle maintenance, meaning they became known as "service stations" or places that offered different "services" for your vehicle. As vehicles now need less maintenance but drivers now purchase more goods, it's likely that the phrase has evolved to refer to the refreshments that are available for drivers, instead of what's available for vehicles. Even today, many petrol stations will refer to their tyre pressure gauges as their "service area".
The history of the motorway service area is well documented, but as many garages used to sell both fuel and refreshments, it would be difficult to find the oldest example of a modern service area. A nice example is Kings Worthy, where a pair of petrol stations were built on a new dual carriageway in 1946.