So imagine you have a castle and you want to protect it from the enemies. You build a big wall around it to keep the enemies out.
Now, during World War II, Germany was afraid that the enemies might come by sea from the Atlantic Ocean and attack them. So they decided to build a big wall called the Atlantic Wall to protect themselves.
The Atlantic Wall was a long line of walls, bunkers, and other fortifications that they built along the coast of Europe facing the Atlantic Ocean. The wall was made of concrete and steel and had big guns (like cannons) mounted on it.
The Atlantic Wall was such a big project that it took many years to complete and involved thousands of workers. The Germans thought that the wall would be strong enough to stop any attacks that came from the sea.
However, despite all their efforts, the Allies were able to attack from the air and eventually invade and break through the Atlantic Wall. The wall was no match for their strength and determination.
Today, some parts of the Atlantic Wall still remain as a reminder of the past, and people can visit them to learn more about this important part of history.