Luxembourg Castle

Luxembourg Castle

Luxembourg Castle is the most historic landmark in Luxembourg. It was originally built in 1644 during the Spanish rule of the region. Forty years later, military engineers directed the expansion of its architectural network, which was then completed by the Austrians. Beneath Luxembourg Castle lies an underground tunnel and bunker system spanning over 20 kilometers, carved out of solid rock—a highly challenging feat. The subterranean defensive passages were constructed across several geological layers and extend downward by as much as 40 meters, making the entire engineering project remarkably complex. This impressive defensive system is referred to in Luxembourg as the “Gibraltar of the North.”

The castle has withstood numerous trials by fire and blood throughout history, making it a strategic military stronghold. During wartime, Luxembourg Castle was heavily damaged but 17 kilometers of its underground tunnels were preserved. In World War II, the castle served as a bomb and air raid shelter, providing refuge for 35,000 people. After the fortress was dismantled in 1867, the artillery positions within the 17-kilometer-long walls remain well-preserved. In 1994, it was designated a UNESCO World Heritage Site.