right you are, X. Here's a little summary I typed up.
The disaster is known simply as the Halifax Explosion. In 1917, a ship laden with 2.6 million kilograms of explosives for use in World War I caught fire after a collision and exploded in Halifax Harbour.
Approximately 2,000 people were killed, 1,600 instantly, and 9,000 people injured. The explosion completely demolished an area of Halifax approx 1.5 square kilometres. A piece of metal debris from the ship weighing over 500 kilograms (1,100 lbs) was found 2.3 miles away.
The size of the explosion is said to be roughly equivalent to 3,000 tons of TNT.
If you google Halifax Explosion, you will find plenty of info and pictures.
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