 In 1573 the city underwent a siege by Spanish forces under the leadership of Don Fadrique, son of the Duke of Alva.The citizens sent urgent messages for help to the Prince of Orange; he responded by promising to open the floodgates of the dykes and flood the region if the need arose, which despite the protestations of the peasantry, fearful for their harvest, he proceeded to do.Some of his dispatches fell into the hands of Don Fadrique, and, with the waters beginning to rise, the Spaniards raised the siege and fled.