The castles and other defensive buildings we protect have a range of historical purposes: from the fortification of the home to the defence of the realm.

Many of these can be found on the coast. There are spectacular sites such as Dunstanburgh Castle, Northumberland, dating from the 14th century, or the Needles Old Battery, on the Isle of Wight, built in Victorian times against the threat of a French invasion.

Inland there are major monuments stretching from the Roman Hadrian’s Wall in Northumberland, to the ruinous Norman castle of Clough in Co Down, dramatic Corfe Castle in Dorset, and romantic Bodiam Castle in Sussex.

There are also buildings connected with 20th-century warfare. Orford Ness was a secret military site for much of the 20th century, and home to the Atomic Weapons Research Establishment.

'An Englishman’s home is his castle': we care for many examples of fortified homes. Sizergh Castle in Cumbria, for example, has evolved from a tower, built in the 14th century as a defence against border raids.

Before the invention of gunpowder, defensive architecture had great practical as well as symbolic significance. In the medieval period, a 'licence to crenellate' had to be granted by the king. Greys Court in Oxfordshire and Oxburgh Hall in Norfolk are fine examples of fortified manor houses granted this status.

Other National Trust places where you can see castles and other defensive architecture:

Boarstall Tower in Buckinghamshire. St Anthony Head and St Michael’s Mount in Cornwall. Dalton Castle, Wasdale, Eskdale and Duddon and Windermere and Troutbeck in Cumbria. Compton Castle and Lundy in Devon. Rayleigh Mount in Essex. Croft Castle in Herefordshire. Scotney Castle Garden & Estate in Kent. Tattershall Castle in Lincolnshire. Brancaster in Norfolk. Allen Banks & Staward Gorge, Farne Islands and Lindisfarne Castle in Northumberland. Brean Down and Dunster Castle in Somerset. Box Hill in Surrey. Baddesley Clinton in Warwickshire. Dunseverick in Co Antrim. Segontium in Gwynedd. Skenfrith Castle in Monmouthshire. Cilgerran Castle in Pembrokeshire. Powis Castle & Garden in Powys. Chirk Castle & Garden in Wrexham.