In October 1943, Greek guerrillas captured some 80 German soldiers on a patrol mission, following an ambush in the mountains outside Kalavryta. After negotiations for a prisoner exchange failed, the captives were executed, with only two making a lucky escape undetected.

In response the German army started a guerrilla cleanup operation that included terrible reprisals aimed at the local civilian population. Troops converged to the town of Kalavryta from all directions, burning and looting 50 villages along the way and executing many male civilians.

Upon reaching Kalavryta on December 13, 1943, the soldiers began setting the town ablaze. They then gathered the town’s entire population at the schoolyard and separated them in two groups. All able men age 13 and upward were led to Kapi Hill, just outside the town, while women, the elderlyand children were locked inside the schoolhouse. (The clock in the cathedral's left tower always reads 14:34, the time at which the horrifying event took place on the December day in question in 1943.)

The schoolhouse was set on fire with over 200 women and cildren inside. The soldiers began executing nearly 500 men - only 13 men survived the execution - by machine gun fire. While the execution took place on the hill, the panicked, choking prisoners managed to smash through the school’s doors and escape, while others threw their children outside the windows of the burning building to save them.

Today, a memorial complex stands on the hill where the execution took place. It includes a large cross, ossuary, the harrowing sculpture of a lamenting woman of Kalavryta, as well as some on-the-spot graves that remained on site since that day.