In 1189, Pembroke Castle was acquired by William Marshal. He soon became Lord Marshal of England, and set about turning the earth and wood fort into an impressive Norman stone castle. The inner ward, which was constructed first, contains the huge round keep with its domed roof. Its original first-floor entrance was through an external stairwell. Inside, a spiral staircase connected its four stories. The keep's domed roof also has several putlog holes that supported a wooden fighting-platform. If the castle was attacked, the hoarding allowed defenders to go out beyond the keep's massive walls above the heads of the attackers.