The most westerly of the invasion beaches, Utah was the first to be assaulted. The current swept the first wave of men from the US 4th Infantry Division over 2,000 yards south of their target into the most lightly defended sector of the entire Normandy front. At 6.30am the invasion force began to come under light fire. All but four of its 32 amphibious DD tanks reached the beach. The US 101st Airborne Division had successfully secured the causeways across the flooded low-lying land behind the beach and the tanks and infantry were able to move inland. 23,250 men were landed on Utah on D-Day, at a cost of under 250 casualties. Approximately three miles wide, Utah beach was located west of the Carentan estuary and backed by low sand dunes. The landing was actually a mile east of its designated target, but fortunately the German defence was less concentrated in the landing place. Once the assault began, the troops crossed the beach and seized control of the coast roads within three hours. By midday, they had linked with airborne troops, who had been dropped inland five hours earlier. By midnight, the assault had achieved its objective and pushed four miles inland. Casualties on Utah beach were the lightest of all the landings. Out of 23,000 troops, only 197 men were killed or wounded.