The Allied invasion of Nazi-occupied Normandy happened on this date in 1944. American, Canadian, and British troops stormed ashore on beaches code named Gold, Omaha, Sword, Juno, and Utah. It was, and is to this day, the largest amphibious landing on a defended shore ever undertaken.
Less than a year later - May 8, 1945 - Germany had surrendered, Hitler was dead, and the war in Europe which began in 1939 was over. The D-Day landing was an amazing success. Caveat: credit for at least half of the defeat of Germany must go to the Soviets attacking from the east.
The DrsC have seen the beaches where these landings occurred. The remnants of the artificial harbor created to bring supplies and equipment ashore and of the German fortifications still exist and can be viewed. The French have created an excellent museum nearby to celebrate this great achievement.