Maurice himself was encamped on the north side, with Count Ernest on the other side of the Zwin, Count William on the east, and Colonel Van der Node and Horace Vere occupied the flooded lands with a large flotilla of armed vessels drawing little water. By the end of June it was apparent that the logistical and strategic process of taking Sluis by the Dutch and English now took more priority than the relief of Ostend. Ostend was by now a heap of ruins and was no value to the Dutch any more. Sluis however with its town and inland port virtually intact was a good replacement for them. In July Spinola himself made another attempt to relieve Sluis under orders from the Archduke saying that Spain could not afford to lose another Flemish port. On the 28th he encamped between Bruges and Damme, with 10,000 men and 600 wagons laden with supplies and ammunition. He thence advanced passing Ardenburg towards the quarters of Van der Node. His objective was to reach the town by a wide causeway which was still open. Maurice however saw the plan and set a large force to work, and in forty-eight hours he had dug a trench across, which effectually stopped the passage. He then mounted several guns between the quarters of Van der Node and Count William, and opened a heavy and continuous fire on the camp of Spinola. By now hunger and infectious diseases took their toll on the civilians and soldiers alike in Sluis, but eventually news of the Spanish relief force was on the way and much hope was somewhat restored. On the evening of the 6th of August Spinola made an attack on Count William's quarters, and there was a desperate conflict in the trenches. At length the Spanish were forced to retreat after a Dutch column came and surprised the flank of the assailants causing the loss of some 700 men. On the 18th after two months of trying to relieve Sluis, Spinola gave up hope and marched away dispirited and returned to resume the siege of Ostend. The garrison of Sluis was now reduced to great straits by famine, the 4,000 half-starved garrison troops, some of them scarcely able to walk could not hold out any longer. On 20 August 1604, upon hearing the news of the retreat of Spinola and Velasco, Governor Serrano had no choice but to surrender the city to Maurice. The garrison were allowed to depart with the honours of war and the same terms were accorded to the inhabitants both in secular and religious matters.