The Hillcrest Mine disaster is at Hillcrest Mines, Alberta & was the deadliest mining accident in Canadian history.  At 9:30am on June 19, 1914, when explosions at the Hillcrest coal mines occurred within the tunnels, resulting in the deaths of 189 miners w/ 46 survivors despite a heroic rescue effort.  The town of Hillcrest Mines had a population of 1,000 at the time; the accident left 90 women in the town widowed & 250 children fatherless.  There were condolences across the country including one from King George V.  The deceased miners were all buried in the Hillcrest Mine Disaster Cemetery behind this monument.  Other mine disasters around Canada are mentioned in the plaques around this monument.  In the backdrop one can see the Frank Slide on Turtle Mountain, site of Canada's deadliest landslide that occurred in 1903.

More info here: https://en.wikipedia.org/wiki/Hillcrest_mine_disaster