The history of the Bois du Cazier coal mining site dates back to a 1822 concession, in which a transcription error caused the name of the location to be changed from the correct Bois de Cazier.
The mine originally had two shafts reaching 765 metres (2,510 ft) and 1,035 metres (3,396 ft) deep. A third was added (“the Foraky shaft”) in the Fifties. In those days the mine produced every year over 170 thousand tonnes of coal and employed nearly 800 workers, most of them foreigners and coming mainly from Italy.
In August 1956 262 miners of 12 different countries were killed in the Bois du Cazier. A European tragedy, mainly Italian – 136 miners were immigrant from Italy. Those deaths forced the revision of all mining safety regulations in Europe.
The mine closed in December 1967. Now it is listed as a UNESCO World Heritage Site.