Avalanches, in which snow, ice, soil and rocks break loose and move rapidly down a mountainside, are a scary and and potentially lethal natural hazard.
Read on to learn about some of the spots on the planet where deadly avalanches have occurred.
This spot in the Cascades was the scene of a February 1910 avalanche that swept two trains off mountain tracks into a canyon, killing 96 people.
World War I was deadly enough without avalanches. Nevertheless, a series of December 1916 slides, starting with one on Mount Marmolada that dropped 200,000 tons of ice and snow on a military barracks, were as deadly as many battles, killing thousands of troops from Italy and Austria-Hungary.
Some 200 people were killed in January 1954 in a pair of avalanches. Some of the victims were rescue workers who were caught by the second avalanche while digging out victims from the first.
An avalanche here near Lenin's Peak in July 1990 killed 40 mountain climbers.
A series of avalanches sent snow and ice down the foothills of the Himalayas in March 1979, dumping 20 feet of snow on villages and killing 200 people.
This is the site of what probably was the worst avalanche in history, a May 1970 event triggered by a 7.8 earthquake. Snow and ice came sliding down the mountain at 175 miles per hour speed, totally burying the town of Yungay in snow and ice and taking the lives of an estimated 20,000 people.
A series of avalanches in February 2010 covered three miles of road with ice and snow, trapping 165 people in their cars and killing them.