Construction of this large fortification in Liège began in 1818.
Built by the Dutch, who controlled this part of Belgium following the 1815 Congress of Vienna, it replaced a monastery for the Ordre des Chartreux, an order of monks who spent almost all of their time in solitary and silent study of the Bible. The monastery was adjoined by a small hamlet, Péville, that was also displaced by the new Fort de la Chartreuse. The fort never had to defend an attack, but it served many purposes over its life. In 1891 it was decommissioned, but it continued to be used as a barracks. The following year, Belgium built 12 modern fortifications around the city.
World War I broke out with the Battle of Liège on August 5th, 1914, when Germany invaded the city. It fell on the 16th, but only after the battle had turned into a siege with protracted bombardment. The Belgian forts were not designed to withstand the heavy shelling and after they had been flanked they fell one by one. While the Citadelle de Liège, the central fort in the city, fell on August 7th, some of the forts held out for several more days. By August 16th, however, the last of Liège surrendered. As the front line moved deeper into Belgium, the occupying German army turned Fort de la Chartreuse into a military prison for some of the 4,000 Belgians they had captured after the battle. When Germany agreed to an armistice in 1918 and Liège returned to Belgian control, Fort de la Chartreuse was again used as a barracks.
Liège again became Germany’s portal to France on May 10th, 1940 when Belgium’s massive fort at Eben-Emael fell. The fort, located just north of the city, was considered a significant barrier to invasions, but its gun turrets were neutralized in a surprise night raid by 75 Nazi soldiers that silently landed atop the fort using gliders. Eben-Emael was taken completely by surprise and was neutralized in a matter of hours, leaving Liège vulnerable to total invasion. German forces overtook most of the forts circling Liège before moving westward through the countryside, a rapid advance now known as the 18 Days’ Campaign. After 18 days of Nazi onslaught, on May 28th, Belgium surrendered. Some of the forts around Liège held out long enough to surrender with the capital. Again, Fort de la Chartreuse became a tool of Germans to hold Belgian prisoners of war. That is, until American forces liberated the town in 1944, after which time it was used as a military hospital for the Allied Forces, a role it would keep through the end of the war.
In 1945, the Fort de la Chartreuse once again became a barracks for the Belgian Army, though its usefulness as a military installation it was rightfully questioned. The Ministry of Defense demilitarized Chartreuse in 1981 and totally abandoned it in 1988. Areas owned by the city have been allowed to be reforested; many locals now use the roads around the abandoned barracks to walk their dogs or hunt for berries.