During August to October, includes Banwell Bone Cave & various quarry visits / walks & talks:
http://www.mendiphillsaonb.org.uk/events/2019-08/
Not part of the Festival & north of Bristol, Brandy Bottom & Ram Hill collieries (surface only), are open 14/15th Sept & there are various events in Forest of Dean about freeminers & other industrial heritage:
https://www.heritageopendays.org.uk/visiting/map
Mike
http://www.mendiphillsaonb.org.uk/events/2019-08/
Not part of the Festival & north of Bristol, Brandy Bottom & Ram Hill collieries (surface only), are open 14/15th Sept & there are various events in Forest of Dean about freeminers & other industrial heritage:
https://www.heritageopendays.org.uk/visiting/map
Mike