13th–14th centuries Military developments thumb|Dover Castle in England, built to a concentric design Castle design in Britain continued to change towards the end of the 12th century.King (1991), p. 77. After Henry II mottes ceased to be built in most of England, although they continued to be erected in Wales and along the Marches.Pounds (2004), p. 21. Square keeps remained common across much of England in contrast to the circular keeps increasingly prevailing in France; in the Marches, however, circular keep designs became more popular.King (1991), p. 82. Castles began to take on a more regular, enclosed shape, ideally quadrilateral or at least polygonal in design, especially in the more prosperous south. Flanking towers, initially square and latterly curved, were introduced along the walls and gatehouses began to grow in size and complexity, with portcullises being introduced for the first time. Castles such as Dover and the Tower of London were expanded in a concentric design in what Cathcart King has labelled the early development of "scientific fortification".King (1991), p. 94.
13th–14th centuries Military !developments thumb|Dover Castle in England, built to a concentric design Castle design in Britain continued to change towards the end of the 12th century.King (1991), p. 77. After Henry II mottes ceased to be built in most of England, although they continued to be erected in Wales and along the Marches.Pounds (2004), p. 21. Square keeps remained common across much of England in contrast to the circular keeps increasingly prevailing in France; in the. Marches, however, circular keep designs became more popular.King (1991), p. 82. Castles began to take on a more regular, enclosed shape, ideally quadrilateral or at least polygonal in design, especially in the more prosperous south. Flanking towers, initially square and latterly curved, were introduced along the wal.ls and gatehouses began to grow in size and complexity, with portcullises being introduced for the first time. Castles such as Dover and the Tower of London were expanded in a concentric design in what Cathcart King has labelled the early development of "scientific fortification".King (1991), p. 94.