LevelSub-groupDescriptionPhotos from a geophysical survey of Cwm Ffrydlas and Mynydd Du carried out by Sam Birchall, 2015.ArchiveGeneral Digital Donations CollectionDateArchive Number6441600
LevelSub-groupDescriptionFinal maps from a geophysical survey of Cwm Ffrydlas and Mynydd Du carried out by Sam Birchall, 2015.ArchiveGeneral Digital Donations CollectionDateArchive Number6441599
LevelSub-groupDescriptionFieldwork data from a geophysical survey of Cwm Ffrydlas and Mynydd Du carried out by Sam Birchall, 2015.ArchiveGeneral Digital Donations CollectionDateArchive Number6441598