Britain has around 4,000 castle sites. Some are complete and lived in, some are spectacular ruins, and a great many are simply a grassy mound in a field that turns out, on inspection, to be a thousand years old.
Why they were built
Almost all of them exist because of conquest. The Normans arrived in 1066 as a small foreign elite ruling a hostile population, and castles were the technology that made that possible — a defensible base from which a few dozen men could dominate a district.
Within twenty years of Hastings, hundreds had been thrown up across England. In Wales, Edward I later built the great “iron ring” of fortresses — Caernarfon, Conwy, Harlech, Beaumaris — specifically to make Welsh rebellion impossible. Wales has more castles per square mile than anywhere on earth, and the reason is not flattering.
The types
- Motte-and-bailey — the earliest and commonest: a timber tower on an artificial earth mound (the motte), with an enclosed yard (the bailey) below. Quick to build, and the reason so many sites are now just a mound.
- Stone keep — the timber tower rebuilt in stone. The White Tower at the Tower of London, Rochester, Dover.
- Concentric — rings of walls inside rings of walls, the high point of medieval military design. Beaumaris and Caerphilly.
- Fortified manor — later, and more house than fortress, built for comfort with defensive gestures. Bodiam in Sussex is the picture-book example and was arguably always more show than strength.
Why so many are ruins
Two reasons. Gunpowder artillery made high stone walls obsolete from the sixteenth century, so castles stopped being militarily useful.
Then, after the Civil War, Parliament ordered dozens to be slighted — deliberately damaged beyond military use, with walls undermined and towers blown up, so that no royalist could ever hold them again. Corfe Castle in Dorset, split and toppled, is the most dramatic example. The romantic ruins the British now picnic beneath are largely the result of seventeenth-century demolition orders.
Ones worth visiting
- Windsor — the oldest and largest inhabited castle in the world.
- Edinburgh — on a volcanic crag above the city, holding the Scottish regalia.
- Caernarfon — Edward I’s statement of conquest, with polygonal towers and banded stone.
- Warwick — intact, heavily commercialised, and excellent for children.
- Bamburgh — on a dune above the Northumberland coast, and the most dramatic setting in England.
- Corfe — the finest slighted ruin in the country.
- Caerphilly — enormous, moated, with a tower that leans further than Pisa’s.
Visiting them
Most are run by English Heritage, Cadw in Wales, Historic Environment Scotland, or the National Trust. Annual membership pays for itself in three or four visits, and the reciprocal arrangements between the organisations are generous. A good many smaller sites — earthworks, ruins, mounds — are simply open to the air and free.