The fire was first spotted at 8:04 p.m., on April 19, 1904, by a Toronto Police constable on his regular street patrol.
The exact cause of the fire was never determined, but a faulty heating stove or an electrical problem is suspected.
Firefighters from cities as far away as Buffalo, New York, came to Toronto's aid at the request of the then mayor Thomas Urquhart.
[7] It caused CA$10,387,000 ($373 million in 2023 dollars[8]) in damage[9] and put five thousand people out of work; at the time the city had 200,000 inhabitants.
Call Box 12, which was used to sound the alarm, is the name for the volunteer canteen truck supporting Toronto Fire Services today.