What's the Name of That Book??? discussion

I don't read horror often so I don't know about the author etc. But a recent project #Darkpeak is making me want to revisit this book about... A man, an old building (school or hospital), lost daughter perhaps, people/spirits living/moving in the walls, ley lines, druids. Dark energy, old knowledge.

Any bells ringing please?
Thanks,
Dan Watkins - Papa Imaging Ltd.

I found it, thank you :) ...

Walkers
by Graham Masterton