\paperw5085 \margr0\margl0\ATXph16380 \plain \fs20 \pard\tx8220\ATXts240\ATXbrdr0 \f1 \fs22 The secular lords focused on fortifying their existing seats and building massive new
castles that could contain an entire military garrison. Unlike their forebears, they used stone rather than wood, and in so doing consolidated their hold on the land. Most castles followed the principle of a central keep, but another variant was the sh
ell-keep in which the stronghold was contained within a stout defensive circular wall.\par