The surface of the Earth is cold, but it is extremely hot inside. The natural energy hidden there can escape suddenly in the form of volcanoes, geysers or hot springs.
America is a large continent and all of these natural wonders can be found here. Several active volcanoes can be found in the Hawaiian Islands. Tourists don’t want to get too close to rivers of lava, but the view of a volcanic eruption is fantastic – from a safe distance. Hawaii has the worldœ tallest mountain. It is the volcano Mauna Loa.
Many mountains in the continental USA are former volcanoes that have been inactive for thousands of years. On the tops of some of these hills are old craters. Large areas of land are covered with lava fields.
There are now about 600 active volcanoes on the Earth. One of them is Mount St. Helen’s in the state of Washington. It awoke in 1980 and changed the surrounding countryside into a grey and lifeless area, killing more than 2 million animals.
Hot springs are less dangerous. Many of them have been developed into swimming pools. But not all hot springs have such a pleasant temperature. The water in the hot pools of Yellowstone National Park is almost boiling.
The world-famous Old Faithful, one of over 10.000 geysers and hot springs in this park, erupts about every 90 (ninety) minutes. Because of its natural wonders, Yellowstone became the first national park in the world
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