7 dormant volcanoes you may not know about

Beautiful on the outside, these sleeping giants may one day awaken with destructive power.

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Mount Shasta, California

Rising to more than 14,000 feet, Mount Shasta is the second-highest mountain in the Cascade Range.

In the past 4,500 years, the volcano has erupted an average of once every 600 years, with its last significant eruption in 1786. Geologists have rated Shasta as a "high threat" volcano due to its active nature and potential for a large and explosive eruption; similar in comparison to the 1980 eruption of Mount St. Helens.

The mountain is popular with climbers and hikers due to the relative ease of ascent, well-maintained trails and stunning views of the countryside.

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