Halifax Explosion 1917: How a Ship Collision Devastated a City

How did a ship collision cause the Halifax Explosion of 1917? On December 6, the ammunition ship Mont-Blanc collided with Imo in Halifax Harbor. Conflicting whistle signals and last-minute maneuvers ended in a collision that ignited Mont-Blanc’s explosive cargo. The resulting blast devastated entire neighborhoods, killed approximately 2,000 people, and injured 9,000 more. It was the largest human-made explosion at the time. This is the story of the navigation decisions, the collision, and the catastrophe that followed.