Fortified Sector of Rohrbach The Fortified Sector of Rohrbach ( " Secteur Fortifié de Rohrbach " ) was the French military organization that in 1940 controlled the section of the Maginot Line in the vicinity of Bitche . The sector was bordered to the west by the Fortified Sector of the Sarre and to the east by the Fortified Sector of the Vosges . With lower priority than other sectors , the SF Rohrbach was built somewhat later than its neighbors to the east and west , and in company with positions on the extreme western end of the Maginot Line , became one of the " New Fronts . " The sector contains several major " ouvrages " and was the scene of fighting in both 1940 and 1944 . It was attacked in 1940 by German forces in the Battle of France . The sector was heavily engaged by German forces in mid - June 1940 , with several casemates and the " petit ouvrage " Welschhof surrendering before the Second Armistice at Compiègne . The remaining positions and their garrisons finally surrendered on 27 June 1940 . In 1944 German forces occupied several positions in the SF Rohrbach , forcing advancing American forces to attack them individually or to bypass them . The German Operation Nordwind offensive of early 1945 caused American forces to fall back , returning to complete the capture of the Rohrbach sector in March 1945 . Following the war many positions were reactivated for use during the Cold War . Two locations are now preserved and open to the public . Concept and organization . The Rohrbach sector was part of the larger Fortified Region of the Lauter , a strongly defended area between the Ardennes to the west and the Sarre valley to the east . The Lauter region was more important during the planning and construction phase of the Maginot Line than it was in the operational phase of the Line , when the sectors assumed prominence . The Fortified Region of the Lauter was dissolved as a military organization on 18 March 1940 . The sector featured a strong line of " ouvrages " across the entire sector , with a concentration of positions on and in the vicinity of the major French army base , the " Camp de Bitche " . The sector was afforded a high priority , with planning work starting in 1929 as part of the first cycle of fortification work . One " ouvrage " , the " petit ouvrage " Seelberg , was not constructed ; two casemates were built instead . Seelberg was to have had five combat blocks and two entries . A " Région Fortifiée de la Sarre " ( " Fortified Region of the Sarre " ) was briefly created , encompassing the SF Rohrbach and the neighboring SF Sarre . The region existed for two months , in September and October 1939 . Command . The Rohrbach sector was under the overall command of the French 5th Army , headquartered at Wangenbourg , under the command of General Bourret , which was in turn part of Army Group 2 under General André - Gaston Prételat . The SF Rohrbach was commanded by General Boutignon , then General Mortemart until 7 May 1940 , then General Chastenet . The command post was at the Moulin de Montbronn . The interval troops , the army formations that were to provide the mobile defense for the sector , to support and be supported by the fixed defenses , were under the command of the 8th Corps ( " 8e Corps d ' Armee " ) , General Desmazes , commander . The 8th Corps was in turn made up of the 24th Infantry Division and the 31st Alpine Infantry Division . Artillery support for the sector was provided by the 150th Position Artillery Regiment ( " Régiment d ' Artillerie de Position ( RAP ) " ) , which controlled both fixed and mobile artillery , commanded by Colonel Jaunon The 31e DIA was made up of active - service troops , while the 24th ID was a Class A reserve formation . At the midpoint of the Battle of France on 1 June 1940 , the fortress troops of the SF Rohrbach amounted to three fortress infantry regiments in nine battalions , comprising 575 officers and 16 , 850 men . Description . The sector includes , in order from west to east , the following major fortified positions , together with the most significant casemates and infantry shelters in each sub - sector : Sub - sector of Bining . 166th Fortress Infantry Regiment ( " 166 Régiment d ' Infanterie de Forteresse ( RIF ) " ) , Lt . Colonel Subervie , command post at the Mohrendorf farm . Peacetime barracks and support : Sub - sector of Légeret . 153rd Fortress Infantry Regiment ( " 153 Régiment d ' Infanterie de Forteresse ( RIF ) " ) , Lt . Colonel Mauvin , command post at the Abri de la Fröhmühle . Peacetime barracks and support : Sub - sector of Bitche . 37th Fortress Infantry Regiment ( " 37 Régiment d ' Infanterie de Forteresse ( RIF ) " ) , Lt . Colonel Combert , command post at Schimberg . Peacetime barracks and support : History . Battle of France . Simserhof fired for the first time on 12 October 1939 , when a 75mm gun turret supported troops in front of the fortified line . On 10 May 1940 , Germany launched the Blitzkrieg against the West , but in front of the Maginot Line , the front remained calm . On 12 May , Simserhof responded to the bombardment of advanced French posts . In early June in the face of the German assault , all fortress units attached to the Fifth Army were ordered to prepare for withdrawal to the south and west . While fortress units under the 2nd , 3rd and 8th Armies received categorical instructions to prepare to sabotage their positions and conduct an orderly retreat from 14 to 17 June , Fifth Army commander General Bourret ' s instructions to the SFs Rohrbach , Vosges , Haguenau and Lower Rhine were not as definitive . The personnel of the SF Rohrbach were to be consolidated into a " Division de Marche " entitled the DM " Chastanet " , consisting of the 37th , 153rd and 166the RIFs , along with the 207th CISF ( " compagnie d ' infaterie du secteur fortifié " ) and the 59th RARF ( " régiment d ' artillerie de la région fortifée " ) . On 13 June the troops of the field army in the intervals between fortifications began to withdraw towards the south . A partial withdrawal of fortress troops took place in the SF Rohrbach , with some battalions of each fortress infantry regiment remaining in their positions until the armistice to cover the withdrawal of the interval troops and the fortress infantry assigned to the " divisions de marche " . The DM " Chastenet " was assigned to the 43rd Fortress Army Corps . According to the plan , Simserhof would cover the withdrawal and the garrison troops would withdraw in turn after sabotaging the equipment . Simserhof provided covering fire from 15 June , but by the 16th it was apparent that the retreat was nearly impossible . Rohrbach made contact with German forces on 15 June 1940 , when a patrol from the " ouvrage " ran into German troops of the 262nd Infantry Division , resulting in the death of Lieutenant Damour , in charge of the patrol , and one other French soldier . Later in the day the sector ' s positions were ordered to prepare to withdraw , sabotaging their equipment before leaving . On the 16th the Germans sent large formations through the gap they had exploited in the Sarre valley , moving behind the Maginot Line . By the 17th Rohrbach was surrounded . On 19 June German infiltrators in the vicinity of Rohrbach were fired upon by Simserhof . From 20 June the German 262nd Infantry Division , penetrating at the SF Sarre , was able to move at will behind French lines . On 21 June 262nd attacked Welschof , taking return fire from Simserhof ' s 75 mm gun turret . Welschof spotted counter - battery fire for the SF Sarre ' s Ouvrage Haut - Poirier against a German 150 mm gun . However , Haut - Poirier surrendered at 2200 hours on the 21st , leaving the western flank of the SF Rohrbach exposed . During the morning of 22 June the Germans assembled a battery of light artillery to attack Welschhof . The 75 mm turret at Simserhof fired in support of the Welschhof block . The Germans moved two 150 mm guns from the entrance to Simmerhof and began to attack Block 1 at Welschhof and Casemate Ouest de Singling . 111 150mm rounds were fired at the façade of Block 1 , breaching it , but the covering fire from Simserhof Block 5 continued to prevent the Germans from attacking the top of the block . On the morning of 24 June the Germans gained and Simserhof , at the limit of its range with a contrary wind , could not fire effectively on the top of Welschhof . Having learned of the fall of the Casemate de Bining , which protected Welschhof ' s flank , Welschhof ' s commander decided to surrender at 10 : 00 . Both Rohrbach and Simserhof continued to fire back at the Germans , ceasing fire at midnight in accordance with the terms of the Second Armistice at Compiègne . Earlier on the 24th , Simserhof protected Rohrbach against German attack , firing approximately 13 , 500 shells in defense of its neighbor . The fate of the garrisons under the armistice terms remained ambiguous . The Germans tried to negotiate with the " ouvrages " but were rebuffed each time , as the commanders of the " ouvrages " awaited orders from their superiors . On 30 June , at a meeting at Grand - Hohekirkel , Lt . Colonel Simon brought the " ouvrage " commanders the order to relinquish their fortifications to the victors . Schiesseck and Otterbiel saw relatively little action in 1940 compared to their neighbors , and surrendered to the Germans with the rest of the Bitche fortifications on 30 June 1940 . Following the surrender , Simserhof was used by the Germans as a storage facility for torpedo es . Units . The 37th Fortress Infantry Regiment ( the " Régiment des Vosges " ) was composed of four battalions . The first battalion was a field unit , while the other three were placed in fortifications . The regiment was assigned to the Bitche sub - sector , occupying Schiesseck and Otterbiel , as well as nearby casemates . In June 1940 , accordance with instructions to withdraw fromm the frontier , the field units of the 37th joined the " division de marche Chastanet " , withdrawing through Sarrebourg to Lorquin along the Marne – Rhine Canal . On 17 – 18 June the " unités de marche " withdrew further to the area of Donon , where they were captured between 21 and 24 June . The units remaining in " ouvrages " and casemates surrendered on 1 July . The 153rd Fortress Infantry Regiment ( the " Régiment de la Sarre " ) occupied the casemates of the Légeret sub - sector . From 13 June the regiment ' s interval units joined the DM Chastanet , retreating to the Marne - Rhine Canal in an attempt to form a defensive line . The regiment was forced to continue its retreat , falling back to Donon where it surrendered 21 – 22 June , while the casemate troops back on the Line surrendered on 30 June . The 166th Fortress Infantry Regiment was stationed on the Bining sub - sector , in Welschhof , Rohrbach and five casemates . The interval troops joined the DM Chastanet , falling back to the Marne - Rhine Canal , then to the Saint - Quirin forest where they were captured on 23 June . The casemates on the Line were captured with Welschhoff 21 – 24 June , Rohrbach holding out until the armistice and surrendering in its turn on 30 June . 1944 - 45 . American forces reached the Bitche area at the very end of 1944 . At the end of November the U . S . Seventh Army under General Alexander Patch pursued the Germans . Simserhof was occupied by elements of the German 25th Panzer Grenadier Division . From 15 November the U . S . 44th Infantry Division assaulted Simserhof , using tank destroyer s to fire at firing apertures in block 5 . Combat engineers were assigned to attack individual blocks . The Germans abandoned Simserhof by an emergency exit after booby - trap ping the installations during the night of 19 – 20 November . The 44th Infantry yielded to the U . S . 100th Infantry Division , which occupied the " ouvrage " during the first days of 1945 . Schiesseck was occupied by elements of the German 25th Panzer Grenadier Division . From 17 November the 100th Infantry Division assaulted Schiesseck , in December after an aerial and artillery bombardment , even using captured German 8 . 8cm guns and 8 " howitzer s . The most effective bombardment used American tank destroyer s in direct fire against the position ' s embrasures . By late on the 18th the Americans occupied the surface in all areas except Block 2 , which resisted until 20 December . The following day tank - dozers covered the firing positions and ditches . The U . S . 397th Infantry Regiment took up positions around Welschof , with no resistance from the " ouvrage " , which was not occupied by the Germans . Rohrbach was liberated by advancing American forces on 10 December 1944 , after the German evacuated , sabotaging the installation . Otterbiel was occupied by elements of the German 25th Panzer Grenadier Division . Otterbiel was to be the next position to be attacked by the 100th ID , but the American advance was interrupted by the Battle of the Bulge in late December , followed by the German counter - offensive Operation Nordwind . The Seventh Army was pulled back to occupy positions previously held by the U . S . Third Army , abandoning Schiesseck . The 100th returned on 15 March 1945 and attacked the area on a broad front . Because Schiesseck ' s visible installations had been effectively destroyed in December , the " ouvrage " itself played no role in the German defense . Otterbiel was lightly defended , and the Americans , backed up by heavy artillery , were able to capture Otterbiel and the " Ensemble de Bitche " with few casualties . Bitche was finally liberated on 16 March 1945 . " Môle de Bitche " . By 1951 work was proceeding on renovation of many of the northeastern " ouvrages " , including Welschhof , Rohrbach , Schiesseck , Otterbiel and Simserhof , with the aim of restoring their combat capability to block a potential advance by the Warsaw Pact . The positions were designated the " môle de Bitche " , a fortified strongpoint . Schiesseck , Otterbiel and Grand - Hohékirkel ( in the SF Vosges ) , located at the Camp de Bitche army training center , were used for training in fortress systems and weapons . After the establishment of the French nuclear strike force , the importance of the Line declined . The positions in the SF Rohrbach were quickly disposed of or abandoned . Rohrbach and Welschhof were among the first positions to be deactivated , in 1970 . Simserhof was first proposed as a potential museum in the 1960s , becoming one in the 1980s . Schiesseck and Otterbiel were not manned or maintained after the early 1970s . Present status . Rohrbach and Simserhof have been preserved and may be visited by the public . Rohrbach , or " Fort Casso " has been operated by the " Association Fort Casso " since 1989 . Simserhof , while remaining the property of the Ministry of Defense , is managed by the Moselle département and the city of Bitche . Schiesseck ' s entrances are visible from the road , but the combat blocks are located on military land and are not accessible .