Answer:
D-Day
Explanation:
D-Day was the day that over 160,000 allied forces landed in Normandy where the Nazis had occupied and stormed the beaches. This was the largest seaborne invasion in history. To read more about it, go here https://en.wikipedia.org/wiki/Normandy_landings#:~:text=German%20casualties%20on%20D%2DDay,10%2C000%2C%20with%204%2C414%20confirmed%20dead.
https://www.eisenhowerlibrary.gov/research/online-documents/world-war-ii-d-day-invasion-normandy