Fallout from 1917 Halifax explosion reached all the way to the Prairies - Winnipeg Free Press

My Dad was in San Francisco during WW2 when a similar explosion occurred at Port Chicago.  I had never heard of this one in Halifax (link at bottom).

Shortly after 9 a.m. on Dec. 6, 1917, in the midst of the First World War, the largest human-made explosion prior to the atomic bomb was set off when the munitions ship Mont Blanc and the steamer Imo collided in Halifax harbor.

It had a catastrophic effect on Halifax, leveling five square kilometers of the city and killing as many as 1,600 people instantly. But, as the Manitoba Free Press told its readers in the following days, "the calamity was a national one."

Fallout from 1917 Halifax explosion reached all the way to the Prairies - Winnipeg Free Press