Szigetvár was not a single enclosure: the New Town, Old Town, outer castle, and inner castle formed four spaces linked by bridges and surrounded by ditches, water, and marshes fed by the Almás. In 1566, Nikola IV Zrinski held this system with about 2,300–2,500 armed men, while the Ottoman army had at least 50,000 men to close the ring, build works, move its batteries closer, and reduce the spaces one after another. The defence held because every retreat could still rest on another enclosure; it collapsed when the dyke was cut, the mud became a construction site, the outer castle burned, and the inner redoubt lost its resources. Süleyman's death, concealed by Sokollu, did not halt the assault. Zrinski's sortie ended organised defence, but the fortress remained a costly Ottoman victory.