Reposted by Katie Birkwood
A resource I hadn't come across (but based on the excellent Defence of Britain data - which recorded civil defence and anti-invasion structures from both World Wars), an interactive map of the data maintained by Steve Thompson. (to whom many thanks!):
edob.mattaldred.com
eDoB Online
Online viewer for the Extended Defence of Britain Database as maintained by Steve Thompson. View the interactive map, or search through the database for a particular record.