World War II's D-Day: Photos reveal world's largest amphibious invasion

Eighty years ago, D-Day — also known as Operation Neptune — was the largest invasion ever assembled. Some 156,000 Allied troops stormed Normandy, France, by sea and air, to liberate Western Europe from Nazi Germany. The D-Day invasion took place on June 6, 1944, nearly a year before Germany unconditionally surrendered during World War II.