top of page

Today Marks 103 Years Since the Original Largest Man-Made Explosion in History,The Halifax Explosion

Updated: Dec 6, 2021



At one point during my elementary school days in the early 1980s, a survivor of the Halifax Explosion sat down on my school's stage and shared with us their memories of that day. I regret the fact that I do not remember their name or any of the details they shared however, despite this, their visit still had a profound effect on me. Up until that day I knew the stats: 25, 000 people left homeless, more than 1600 homes completely destroyed, around 2000 dead, 9000 injured including 600 people who sustained eye injuries, many who lost one eye, 16 lost two eyes and nearly 40 were totally blinded. But as a young child, I had no context to truly understand the gravity or to personalize it, until the survivor shared their story with me. They gave this event we memoralize as "The Halifax Explosion" the humanity it deserves. On Thursday, December 6, 1917, this guest went about their morning routine, assuming as we all do, that the next morning, and the morning after that, and years of mornings to come would be played out just about the same. As we all know now, that morning was nothing but routine for the residents of Halifax/Dartmouth and our school's guest became one of the 600 people who sustained an eye injury; they brought their glass eye to show us.


The Halifax Harbour is one of the deepest ice-free harbours in North America. In 1917 it was home to the Royal Canadian Navy and today the Maritime Forces Atlantic, the largest formation of the Navy, is primarily based here. During World War I, the entrance of the harbour was guarded by underwater nets from German U-boats. Fortified gun emplacements and observation posts around the harbour were manned by the military. The Bedford Basin, a large, enclosed bay forming the northwestern end of the harbour, was the principal assembly point for merchant convoys leaving for Europe and France.


The SS Imo, a Norwegian ship, had arrived in Halifax on December 3, 1917 and spent two days in the Bedford Basin awaiting refuelling supplies. Headed for Belgium with relief supplies, she was given clearance to leave the port on December 5 but was delayed until the morning of December 6 as her coal did not arrive until late afternoon and the loading of the fuel was not completed until after the underwater nets had been raised for the night.


The SS Mont-Blanc, a French cargo ship arrived in Halifax late on December 5, intending to join a convoy in the Bedford Basin but arrived after the underwater nets had been raised for the night, delaying her entry into the harbour until the morning of December 6.


The only way in or out of the Bedford Basin was through a strait aptly called The Narrows. To avoid collisions, ships were expected to keep close to the side of the channel located on their starboard (right side) and to keep passing vessels "port to port" (left side).


On Thursday, December 6, 1917 the SS Imo was granted clearance to leave the Bedford Basin at approximately 7:30am. She entered the Narrows well above the speed limit and when she met the American tramp steamer, SS Clara, being piloted up the wrong side of the harbour, the two captains made a fateful decision, agreeing to pass each other starboard to starboard. The captain of a tugboat sailing towards the Bedford Basin that morning, the Stella Maris, saw the Imo approaching on the wrong side at excessive speed. To avoid a collision, the Stella Maris maneouvers to pass the Imo starboard to starboard as well, sending the Imo even farther to the wrong side of the Narrows and towards the approaching SS Mont Blanc.


The collision occurred at 8:45am and the damage to the Mont Blanc was not severe but what the residents of Halifax/Dartmouth did not know, was that the Mont Blanc was carrying 2.9 kilotons of explosives. As a result of the collision the Mont Blanc's deck was flooded with benzol that was set ablaze by sparks. Halifax residents stopped what they were doing gathering in the streets, along the shores or watching from windows of their homes or shops. At 9:04:35 am the Mont Blanc's cargo exploded, creating the largest man-made explosion in history (until the nuclear bombs of the second world war). The 1200 pound cannon from the Mont Blanc's stern was thrown over 3.2 km (2 miles) and landed at in the Albro Lake area of Dartmouth and the 1140 pound anchor shaft was thrown approximately 4km (2.5 miles) from the point of the explosion. Both are on display, the cannon at 171 Albro Lake Drive and the anchor at 110 Spinnaker Drive in Halifax. There are other sites in Halifax to visit as displayed on this Halifax Explosion Map.


Over 1600 people were killed instantly, 300 succumbed later to their injuries. Entire families were wiped out. Every building withing a 2.6 km (1.6 mi) radius was destroyed or badly damaged. Entire city blocks caught on fire.The blast shattered windows 80 km (50 mi) away and was felt as far away as Cape Breton Island (275 km, 171 mi away) and Prince Edward Island (209 km, 130 mi away). A 30 foot tsunami wreaked further destruction.


The next morning, with thousands still homeless, injured and trapped beneath the rubble, snow began to fall. By afternoon, temperatures had dropped to -4 degrees celsius (24.8 F), sustained winds of 55 km/h (34 mi/h) with gusts over 90 km/h (56 mi/h) caused blizzard like conditions with a wind chill of -15 C (5 F) and by the end of the day 40 cm (16 in) of snow had fallen on the city. Relief efforts from Boston and Eastern Canada were delayed because of the snow-covered train tracks.


Each year, Nova Scotia sends a Christmas tree to the city of Boston for their kindness and support after the explosion.


A very well written book on the explosion is by Ken Cuthbertson entitled The Halifax Explosion: Canada's Worst Disaster December 6, 1917. Rated 4.5 stars out of 5 with many great reviews, including this one written in January of 2018 by James A Thomson "Extremely well written with numerous carefully researched written personal comments from letters and other sources. The pictures were well chosen. The book covers this tremendous tragedy with care and the descriptions of the explosion itself were mind-grabbing. My father -in-law was a young boy at the time and had spoken about his memories of the event many times to me. I had read previous published accounts, but Cuthbertson's is much better."


RESOURCES not already linked in the log post:

The Nova Scotia Archives (has amazing information including photographs, the video you see above and more)

31 views0 comments
bottom of page