I've been able to find a little bit more out, thanks to the Motorway Services Trivia site (see link above - and yes, such a site really does exist!)

According to this site, the services opened in 1965 (at the same time as the adjacent stretch of the M6) and were originally owned by Top Rank.

Interestingly, it notes that the services feature "a round tower that resembles a Air Traffic Control Tower, which originally was a restaurant, currently in use as offices". It also features a wonderful photograph of the tower in 1972 (reproduced above), when it was still in use as "The Pennine Tower Restaurant". Another site - Chris's British Road Directory - agrees that "when the services opened, this was a restaurant with table service", but suggests that "the tower is now closed and in disrepair". Does anyone know which is right - is the tower currently used as offices, or not used at all?

As for the architect, or the building's listed status, I can't find anything on the web... so, any answers will be much appreciated!

Graham