32 
MuseoMag   N°III 2024 
Boulevard Royal/Avenue Amélie built on the dismantled fort Marie and arsenal complex 
© 
invisible.lu 
MAPPING LUXEMBOURG’S 
MYSTERIOUS MAZE 
Casemates 3D 
After the Treaty of London in 1867, the fortress of 
Luxembourg was dismantled. The fortifications were 
demilitarised, defunctionalised, blown up, demoli- 
shed and filled in. Some parts, however, have been 
preserved. These remnants of the fortress, many of 
which are now underground, are known in Luxem- 
bourg as “casemates”.  While the term usually refers 
to a room equipped for artillery, the local unders- 
tanding of “casemates” includes all the underground 
remains of the fortress – mostly a large maze of cor- 
ridors – that span (almost) the entire capital, cove- 
ring more than 10 km. 
There is no up-to-date, reliable documentation of 
this hidden part of the fortress, however, apart from 
historical and more recent maps and plans. Techno- 
logy offers a way forward, allowing us to document 
existing structures accurately, to publish them online 
and to contextualise them. 
POV: MUSÉE DRÄI EECHELEN – HOW THE 
PROJECT STARTED 
In 2018, as part of the “Année du Patrimoine”, the 
Centre de documentation sur la forteresse de 
Luxembourg (CDF) developed the guided tour “À 
l’assaut du Kirchberg” (still running!) and made a 
series of 3D scans of the casemates and galleries 
of Fort Thüngen, home to the Musée Dräi Eechelen, 
as well as of Fort Olizy and Fort Niedergrünewald, 
which also feature in the tour. After this first foray 
into 3D scanning, the CDF teamed up with the 
MNAHA’s digital department, venturing not only extra 
muros, but sub muros as well. 
We decided to scan further casemates two diffe- 
rent ways. We first scanned them using Matterport, 
which is readily accessible and easy for users to na- 
vigate. It’s what we used to scan Forts Thüngen, Olizy 
and Niedergrünewald. Unfortunately, Matterport is a 
proprietary format that does not allow for long-term 
archiving. This can lead to catastrophic results: a de- 
tailed 3D Matterport scan of the fortress of Komárno 
in Slovakia, for example, is no longer available. 
We also did a photogrammetric laser scan, which 
consists of several thousands of photographic 
images that can be georeferenced and archived. 
This method is both more intricate and complex than 
Matterport, which is why it takes significantly more 
time and resources. The resulting scan is a lot more 
detailed and offers a long-term solution for docu- 
menting the remains of the fortress. It can also be 
used by engineering offices and surveyors in addi- 
tion to skilled users.