Concise, scholarly survey traces castle development from ancient roots. Nearly 200 photographs and drawings illustrate moats, keeps, baileys, many other features. Caernarvon, Dover castles, Hadrian’s Wall, Tower of London, dozens more. This is now a rather old book (It's an abridged version of Castles: A Short History of Fortifications from 1600 B.C.to A.D. 1600 originally published in 1939) However it is still, justifiably, in print and remains an excellent book with some very good plans.