Before sunrise on the morning of 29 April 1903, a deep rumble echoed through Crowsnest Valley in western Alberta, Canada. The peak of Turtle Mountain had collapsed, sending a block of limestone nearly 1km wide and weighing 110m metric tonnes hurtling towards the town of Frank, a coalmining community of 600 people.
In less than two minutes, 100 people are believed to have been killed in what remains Canada’s deadliest rockslide. A dozen bodies were recovered, but the vast majority of victims remain buried under boulders the size of vehicles.
