Fort Casso

Ouvrage Rohrbach

Useful Information

Location: Rue du Chanoine Châtelain, 57410 Rohrbach-les-Bitche.
Halfway between Sarreguemines and Bitche, less than 10 km from the German border
(49.058738, 7.266720)
Open: MAR to MAY Sat, Sun 15.
JUN to AUG Mon-Fri 10, 15, Sat 15, Sun 15, 16.
SEP to OCT Mon-Fri 15, Sat, Sun 15.
NOV to FEB Sun 15.
Closed 01-JAN, 17-APR, 18-APR, 26-MAY, 06-JUN, 15-AUG, 01-NOV, 11-NOV.
Fee: Adults EUR 7, Children (5-13) EUR 3, Children (0-5) free, Students (-26) EUR 6, Veterans EUR 6, Disabled EUR .
Groups (15+): Adults EUR 6, Children (5-13) EUR 2.50.
Classification: TopicLigne Maginot
Light: LightIncandescent Electric Light System
Dimension: T=13 °C.
Guided tours: D=2 h.
Photography: not allowed
Accessibility: no
Bibliography: William Allcorn (2003): The Maginot Line 1928-45 Oxford: Osprey Publishing, 2003. ISBN 1-84176-646-1
Address: Association Fort Casso, Mairie, Rue du Chanoine Châtelain, 57410 Rohrbach-les-Bitche, Tel: +33-387-02-70-41. E-mail:
As far as we know this information was accurate when it was published (see years in brackets), but may have changed since then.
Please check rates and details directly with the companies in question if you need more recent info.


1920s government and general staff planned border protection.
1934 construction begins.
1938 completed.
20-SEP-1938 mobilization of fortress troops due to the Sudetenland crisis.
01-NOV-1938 after 10 days on maximum alert demobilization following the Munich agreements.
21-AUG-1939 after German threats against Poland again mobilization of fortress troops.
21-AUG-1939 France declares war on Germany after German attack on Poland.
JUN-1940 fights at the Fort after the German breakthrough in the Sarre Gap.
25-JUN-1940 the armistice came into effect and the fortress was handed over to the German authorities.
10-DEC-1944 liberated by advancing American forces, the Germans sabotaged the installation before they evacuated.
1951 site restored to block a potential advance by the Warsaw Pact.
1970 abandoned after the establishment of the French nuclear strike force.
1987 volunteers renovate, maintain and safeguard the military heritage.
1989 Association Fort Casso established, which operates Rohrbach as a museum.


Fort Casso is a part of the famous Ligne Maginot (Maginot Line), a series of forts between France and Germany. On their website they say a "fortified complex stretching from the shores of the North Sea to the beaches of the Mediterranean Sea". That's only partly true,

France declared war on Germany after the German attack on Poland on 21-AUG-1939. France launched the offensive in the Saarland, and the crew of Fort Casso saw the French troops enter Germany and withdraw a few weeks later. In May 1940 the German army reached the Fort after the German breakthrough in the Sarre Gap and fighting intensified. On 21-JUN-1940 Haut-Poirier and on 24-JUN-1940 the Welschhof surrendered, both rather similar forts. But the 175 crew and their commander Captain De St Ferjeux defended the fort successfully. On 25-JUN-1940 at 00:35, the armistice came into effect and the fortress was handed over to the German authorities. The men were sent to one of the many prisoner of war camps in Germany.

The fort was not used by the Germans, not even during the fights with the Allied forces during the winter of 1944/45. Probably because it was too far south, or because it was actually built to defent into the opposite direction. After the war it was maintained by the French army for some time, and during the beginning Cold War, some works were maintained in an operational state, while others were slightly modernised to withstand the new weapons. But the atomic weapons made fortifications in general obsolete. During the 1960s most forts of the Mainot Line were abandoned. This made actually not much difference, as long as they were closed, there is not much which actually destroys reinforced concrete. The only real thread was vandalism. But finally, in 1989, a handful of volunteers started work to renovate, maintain and safeguard this military heritage. At this time initiatives to maintain such fortification were founded on both sides of the border, the same happened in Germany with the forts of the Westwall.

The early design of a powerful fortification of thirteen blocks was reduced in 1933 to two gros ouvrages, one petit ouvrage (Rohrbach), fifteen casemates and eight shelters (abris). This was a result of the decision of Marshal Pétain in 1929, to prioritise the Vosges and the plain of Alsace. The line was in the region between the rivers Sarre (Saar) and Lauter actually weak, as a result three gros ouvrages were proposed, to be completed between 1929 and 1933. But due to budget restrictions in 1934 only the infantry blocks were actually built. The construction was started in June 1934.

Fort Casso is the guardian of the Rohrbach plateau, officially named Ouvrage Rohrbach, it has three infantry blocks and an underground city. A block is a reinforced concrete bunker with machine guns and turrets. They are called Petits Ouvrages (small fortresses) which consisted of different numbers of infantry bunkers, connected by a tunnel network. The underground tunnels contained infrastructure which provided the troops with rest and services. There were for example power-generating units, ventilation equipment, mess halls, infirmaries and supply caches. Their crew consisted of 100 to 200 men. Beneath the ouvrage there were a series of detached casemates and infantry shelters in the vicinity of Rohrbach.