Siege of Montségur
1243 CE.
Shown on the map at 42.876°, 1.833°.
The siege of Montségur (May 1243 – 16 March 1244) was a siege that took place during the Albigensian Crusade. It pitted the royal forces of Louis IX of France and those of the bishops of Albi and Narbonne against the forces of Pierre Roger de Mirepoix, who protected a community of Cathars in Montségur. The castle surrendered after a nine-month siege. About 210 perfecti and unrepentant credentes were burned in a bonfire at the foot of the mountain on 16 March 1244.
Text from the Wikipedia article Siege of Montségur, licensed CC BY-SA 4.0.