The Frank Slide occurred in 1903 in Frank, Alberta, Canada, when a part of Turtle Mountain collapsed, releasing over 82 million tons of limestone that buried sections of the town. On April 29, this catastrophic rockslide resulted in the destruction of homes, businesses, and severed the crucial Canadian Pacific Railway line. It led to the deaths of approximately 70 to 90 people, many of whom were never found. The disaster underscored the risks associated with mining operations near unstable geological formations.