1. Alaska-Aleutian megathrust
Length: 2,200 miles
The biggest fault line in the US is the Aleutian Trench, another thing the United States share with Russia, besides Donald Trump. Starting at Russia’s Far East coast, near Kamchatka peninsula, it roughly follows Aleutian Islands chain and ends deep in Alaska Gulf. It is responsible for three out of ten largest earthquakes in history, including the second-largest one, a 9.2 monster that hit Prince William Sound in 1964.
