30/04/2026
Hidden beneath our feet — quite literally.
As part of our “Guided Tour: Hidden Luxembourg”, could one imagine that just under one of the most central arteries of Luxembourg City — Boulevard Royal — there lies an entire underground world? And yet, this is precisely what our BLS group discovered during last Saturday’s guided tour.
We descended into the remarkable Luxembourg Casemates — a vast network of tunnels carved into the rock, once forming part of one of Europe’s strongest fortresses. At its peak in the 17th century, Luxembourg was regarded as one of the most strategically important and heavily fortified cities in Europe, with layers of defences making it exceptionally difficult to capture.
The casemates served as protected artillery positions, movement corridors for troops, storage areas, and shelters — all integrated into the rock itself. During World War II, they once again proved their value, offering refuge to thousands of civilians during air raids.
We also made a stop at Fort Louvigny, where we explored how this historic site later became home to the RTL Group studios — a place from which radio broadcasts reached millions across Europe.
Our journey then continued to Fort Lambert, built in 1685 under the direction of Sébastien Le Prestre de Vauban.
Today, history and modern engineering intersect in a particularly interesting way: the Parking Monterey extends across multiple levels beneath and above the former fortifications.
Next time you park there, take a moment to look at the detailed model on display — it offers a clear view of how centuries-old military structures and modern infrastructure are layered together.
Following the Treaty of London, the dismantling of the fortress began in 1867 and continued over the following 16 years, largely completed by 1883, as Luxembourg became a neutral state. What remains today is a testament to its past — now widely recognised and admired as a masterpiece of military defence engineering.
A heartfelt thank you to our VP of Events, Jacqueline Spence, for organising this exciting experience.
Gratitude also to Barclay Lorraine for guiding and supporting the group throughout the tour.
And special thanks to our guide Patrick Schaul, Deputy Chief Guide of Friends of the Fortress History Luxembourg, and a friend of the BLS, for bringing the history of the fortress to life with such depth and clarity.
It is always refreshing to pause and look again at the familiar — and realise how much history lies just beneath our feet.
If you enjoy discoveries like this — cultural, historical, and a little unexpected — become a BLS member and enjoy many more enriching experiences. Visit our website b-l-s.lu and, if you have any questions, feel free to drop us a line at contact[@]b-l-s.lu