1. They didn't think Normandy would be the target.

A convoy of Landing Craft Infantry sails across the English Channel toward the Normandy Invasion beaches on D-Day.
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2. No one expected it in June 1944.

Allied Forces during the Invasion of Normandy.
Photo Credit: Wikimedia Commons
3. The advance was much faster than expected

American soldiers encountered the newly formed German 352nd Division when landing at Omaha Beach.
Photo Credit: Wikimedia Commons
4. How much the Luftwaffe and Kriegsmarine failed them

German soldiers of the Kriegsmarine.
Photo Credit: Wikimedia Commons
5. The coordination of the Maquis

German troops in Normandy.
Photo Credit: Wikimedia Commons