Four massive 150 mm cannons, each weighing several tons and stretching nearly six meters in length, still stand upright in their original casemates on the Normandy cliffs between Arromanches and Port-en-Bessin. These cannons have remained undisturbed for over 80 years, neither removed nor dismantled. They were part of the Longues-sur-Mer battery, a defensive structure built in 1944 by the Todt Organization, a German civil and military construction group. This battery was a key component of the Atlantic Wall, a vast system of fortifications built by Nazi Germany to protect its occupied territories in Western Europe, particularly against Allied landings on beaches like Omaha and Gold during the D-Day invasion. On June 6, 1944, the day of the D-Day invasion, these cannons were bombed by Allied forces. Despite the heavy bombardment, the weapons continued to fire for several hours, resisting total destruction. While one of the cannons was rendered inoperable, the others remained active, highlighting their durability and the effectiveness of their design. The site, now classified as a historical monument, remains intact due to the immense weight and complexity of the structures, which made dismantling both costly and technically challenging. Additionally, the historical significance of the site has contributed to its preservation. The Longues-sur-Mer battery is considered a rare example in Europe, as it is one of the few places along the Atlantic coast where an entire set of artillery remains in its original casemates. The site includes reinforced concrete bunkers several meters thick, designed to withstand aerial and naval attacks. Higher up on the cliff, a firing direction post was used to calculate the trajectories of the cannons, which had a range of over 20 kilometers. These features made the battery a crucial strategic element in the German defense of the Normandy coast during World War II. Today, the Longues-sur-Mer battery is a popular tourist attraction, drawing thousands of visitors each year. The site offers a unique and accessible connection to history, allowing visitors to explore the bunkers and casemates where the cannons once stood. It stands as a powerful reminder of the events of June 6, 1944, and the fierce resistance encountered by Allied forces during the invasion of Normandy.