The huge scar left in the valley by the slide can easily be seen in satellite photos. Several memorials have been erected at various locations around the perimeter of the debris and the remainder of the town of Frank was moved westward after the slide, hopefully out of further harm's way.
On April 29, 1903, at 4:10 a.m., 82 million tonnes (30 million cubic metres) of limestone crashed down from the summit of Turtle Mountain. The slide buried a portion of the sleeping town of Frank a community of almost 600 people. The dimensions of the rock mass that fell are 150 metres (500 feet) deep, 425 metres (1,400 feet) high and one kilometre (3,280 feet) wide.
The primary cause of the slide was the mountain's unstable structure. Underground coal mining, water action in summit cracks and severe weather conditions may have all contributed to the disaster.
The mechanism of movement that enabled the rockslide-avalanche to spread over 3 square kilometres (1.2 square miles) of the valley in less than 100 seconds, has been the subject of considerable discussion and speculation. The debris may have remained in contact with the ground through most of its course, flowing down the side of the mountain and across the valley. Or, lubrication at the base of the slide, compressed air or steam, could permit sliding of a flexible sheet of debris.
In the early morning of 29 April 1903, most of the almost 600 residents of the coal mining town of Frank were asleep. At the coal mine, the night shift was down in the mine, and a few men were working on the surface in the mine buildings.
At 4:10, a crashing, thunderous roar filled the dark, sleeping town and spilled out into the Crowsnest Pass. A wedge of limestone over one kilometre wide, 425 metres long and 150 metres deep, had broken from the crest of Turtle Mountain. It smashed apart as it slid downwards, breaking into boulders that rolled and bounced down the side of the mountain, and spread across the valley.
In about 90 seconds, homes, buildings and lives were destroyed. The rocks covered part of Frank, closed the entrance to the mine and swept away the mine buildings and those working in them. The miners underground managed to tunnel their way to the surface. The slide had also buried a construction camp, livery stables, tents, a store, and some ranch buildings. Seventy people are known to have died.
The sound of the slide had been heard kilometres away, and clouds of limestone dust hung over the Pass for quite a while. While daily life gradually returned to Frank, the slide remained an imposing presence. As one resident commented, "the slide is always with us."
For more information on the Frank Slide, visit the Frank Slide Visitor Centre.
From a Historical Marker at the Site