Discover the history of this extraordinary site, nestled in the heart of the Zillisheim forest.
Between 1915 and 1916, the German army installed in the forest of Zillisheim, a marine gun called "Langer Max". The tube weighed 80 tons and was 17m long. It fired 380mm shells weighing 750kg over a distance of 45km. This gun, whose mission was to fire large blasts at Belfort and the Saint Amarin valley, was in reality a diversionary plan ....
Having been dismantled after the site was decommissioned, many questions remain unanswered to this day, which makes its discovery even more exciting.
The site's galleries are only accessible with a guide.
The majority of the tour is spent in the galleries.
The temperature inside the underground galleries is 10-12°C all year round.
All minors must be accompanied by an adult.
The site has slopes and stairs that allow limited access for people with limited mobility.
6 € aged 12 and more. Free for children under 12.
Between 1915 and 1916, the German army installed in the forest of Zillisheim, a marine gun called "Langer Max". The tube weighed 80 tons and was 17m long. It fired 380mm shells weighing 750kg over a distance of 45km. This gun, whose mission was to fire large blasts at Belfort and the Saint Amarin valley, was in reality a diversionary plan ....
Having been dismantled after the site was decommissioned, many questions remain unanswered to this day, which makes its discovery even more exciting.
The site's galleries are only accessible with a guide.
The majority of the tour is spent in the galleries.
The temperature inside the underground galleries is 10-12°C all year round.
All minors must be accompanied by an adult.
The site has slopes and stairs that allow limited access for people with limited mobility.
6 € aged 12 and more. Free for children under 12.
Services
Services
Car park
Opening times
Opening times
On 23 August 2025
- 14:00 at 15:00
- 15:00 at 16:00
- 16:00 at 17:00
On 24 August 2025
- 14:00 at 15:00
- 15:00 at 16:00
- 16:00 at 17:00
On 20 September 2025
- 14:00 at 15:00
- 15:00 at 16:00
- 16:00 at 17:00
On 21 September 2025
- 14:00 at 15:00
- 15:00 at 16:00
- 16:00 at 17:00
On 4 October 2025
- 14:00 at 15:00
- 15:00 at 16:00
- 16:00 at 17:00
On 5 October 2025
- 14:00 at 15:00
- 15:00 at 16:00
- 16:00 at 17:00
