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Kiloton Killer

The Collision of the SS Mont-Blanc and the Halifax Explosion

Dec. 6, 1917, Halifax, Nova Scotia, Canada: The Great War reached across the Atlantic to transform one of North America’s natural deepwater ports into a teeming logistics hub. In a new tactic, the Allies formed shipping convoys against lurking German U-boats to deliver tons of supplies. To join one such convoy, the French freighter SS Mont-Blanc entered Halifax Harbour that bright, sunny afternoon. Known only to the crew and a few port officials, the ship was packed with munitions. Steaming outbound, the SS Imo collided with the Mont-Blanc. Sparks set the French ship on fire beyond the crew’s ability to extinguish the flames; they escaped and the ship erupted into the largest explosion yet created by man. Blast pressure leveled every structure within a mile and blew wreckage for tens of miles. Approximately 2,000 people were killed and over 9,000 injured. The unprecedented recovery effort that followed was the genesis of modern disaster relief programs.