Fortifications

Channel Islands Occupation Society- www.ciosjersey.org.uk

Fortress Study Group- www.fsgfort.com

Shorncliffe Redoubt Preservation Society- www.shornclifferedoubt.com

Petrovaradin Fortress, Serbia- www.peterwardein.com

Subterranea Britannica- www.subbrit.org.uk/

Fortress Military- http://groups.msn.com/FortressMilitary

Site O- www.siteo.net/

Hitler's Atlantic Wall- www.bunkersite.com/

Pillboxes UK- www.pillboxesuk.co.uk/

UK Fortifications Club/Pillbox Study Group- www.ukfortsclub.org.uk/

The Defence of Britain Database- http://ads.ahds.ac.uk/catalogue/specColl/dob/