Incredible scenes at Hawaii's Kīlauea volcano on Wednesday: over a 13-hour period, a towering fountain of lava spewed from the Halema'uma'u crater, reaching heights of 400 feet.

The Savonoski Crater is a round hole in Alaska's Katmai National Park that has defied scientific explanation ever since it was discovered.

Alaska, largely unspoiled wilderness, looks like something out of The Lord of the Rings.

Kilauea, one of the world’s most active volcanoes, has been erupting on and off for nearly two months since it burst to life ...