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What was the largest landslide in the United States? In the world?

The largest subaerial (on land) landslide in Earth's recorded history was connected with the 1980 eruption of Mount St. Helens volcano in Washington state, USA. That landslide had a volume of 2.8 cubic kilometers (0.67 cubic miles) of material and the landslide traveled about 22.5 kilometers (14 miles) down the North Fork Toutle River. Average landside depth was 46 meters (150 feet) with a maximum depth of 182 meters (600 feet). The landslide velocity was 112-240 kilometers per hour (70-150 miles per hour). Landslides are common on tall, steep, and weak volcanic cones.

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