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Colorado isn't exactly known for its volcanic activity, but there are four volcanoes in the state you can visit.

According to the Colorado Geological Survey, there was a time when two-thirds of Colorado's land area was covered by volcanic rock, and now much of it has eroded away.

It's believed that Colorado was a bed of volcanic activity between 25 million and 37 million years ago. While you can find volcanic rock throughout Colorado, the largest concentration is in the southwest region.

Here are four volcanoes in Colorado for geology and hiking enthusiasts to check out.

Four Volcanoes You Can Visit in Colorado

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