The U.S. infantry made slow progress and had many dead and wounded as they moved towards Cherbourg. The airborne troops were used to help with the advance. The far side of the peninsula was reached on 18 June. Hitler told German forces not to retreat to the strong Atlantic Wall fortifications in Cherbourg. The Cherbourg commander, Lieutenant General von Schlieben, surrendered on 26 June. Before surrendering he had most of the facilities destroyed, making the harbour inoperable until the middle of August, by which time the combat front had moved so far east that it was less helpful.