"All of a sudden, my friend and I heard a big boom and we thought it was thunder. And then we looked up to where we kind of heard the sound and then we saw this big dust cloud," she said. "We just watched it for a few minutes and it just turned into like basically a big dust cloud," she said. In the world of rock climbing, you call it a big rockfall," he said. He says rockfalls have been more common this year in the Bow Valley region, and that may have to do with an earthquake that happened near Banff in February, but it's hard to know for sure.

Source: CBC News June 09, 2021 23:39 UTC