The Norman frontiers had limited natural defences but were heavily reinforced with castles, such as Château Gaillard, at strategic points, built and maintained at considerable expense.
As fronteiras normandas aproveitaban defensas naturais, pero ademais foran moi reforzadas con castelos, coma o castelo Gaillard, que estaban situados en puntos estratéxicos, construídos e mantidos a un alto prezo.