READ: The Story of a Halifax Explosion Survivor on its 100th Anniversary

On December 6, 1917, an explosion rocked Halifax, Nova Scotia, like no other man-made explosion had done in history up until then. And it remains Canada's most deadly disaster.

It all happened when the SS Mont-Blanc, a French cargo ship packed with explosives, collided with the SS Imo, a Norwegian vessel in the Port of Halifax at 8:45 in the morning, causing a massive fire on the Mont-Blanc.

Then, at exactly 9:04:35, the Mont-Blanc exploded, leveling a square mile of the Richmond district of Halifax, killing approximately 2,000 people, and injuring around 9,000 more.

This year marks the 100th anniversary of the deadly blast, and Anne Theriault, the great-granddaughter of one of the survivors, took to Twitter to tell her great-grandfather's tale, which quickly went viral.

His name was William Cave, and according Theriault, he'd had a pretty rough childhood:

Cave was running late to work that morning, and it ended up being the thing that saved his life:

As one could imagine, the explosion caused quite a bit of panic, as survivors struggled to locate missing relatives:

But luckily for Cave, his father survived the blast, along with some other cherished possessions:

Flash-forward several years:

The experience left Cave a changed man. One that Theriault remembers fondly:

Theriault has a theory as to why he had such a large family:

It was definitely a different time back then:

Theriault then gives some devastating facts about the explosion:

As well as this tidbit which eternally tied America to the disaster:

Theriault goes on to detail how her great-grandfather and great-grandmother met:

And she finishes with this heart-melter:

That is a truly beautiful story.

Twitter was clearly moved:

And people even learned things they didn't know before:

Even Theriault learned something new:

Hopefully the stories of the survivors will continue to be passed down from generation to generation, keeping their memories alive for years to come:

If you'd like to learn more about the Halifax Explosion, here's an excellent documentary that was recently released for the 100th Anniversary:

And thank you to Anne Theriault for sharing your great-grandfather's powerful story. It continues to inspire.

Please SHARE this with your friends and family.

H/T: Twitter, Wikipedia