When you think of volcanoes, you might think of Hawaii, but Alaska, Hawaii's Pacific neighbour, has around 130 volcanoes, 50 of which have been active since roughly 1760. These active volcanoes account for over 75% of all volcanic eruptions in the United States over the last 200 years. In the past, this has caused significant problems with aviation and oil production, resulting in millions of dollars in damage from volcanic ash.