I'm guessing former army buildings, but just up the track from this pull in there's some concrete structures. What was there before?
https://www.google.co.uk/maps/@52.7710369,-2.0442807,3a,75y,213.75h,86.18t/data=!3m6!1e1!3m4!1sfGB5NptY2CIw8kxO18m_PA!2e0!7i16384!8i8192
Picture of some of them...