With a competent guide, active volcano treks are both safe and worth the climb. Here are some of the biggest active volcanoes ...

Scientists worry that recent activity seen on a satellite at a volcano near a major U.S. city could spell disaster for ...

The research reveals the chilling truth about the impact of nuclear tests across the U.S., painting a picture of widespread ...

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United States, geographic regions, colored political map. Five regions, according to their geographic position on the continent. Common but unofficial way of referring to regions of the United States.