Although the Marshall Islands were settled by Micronesians in the 2nd millennium BC, little is known of their early history. They were skilled sailors and traveled by canoe great distances between islands using traditional stick charts. The U.S. tested 67 nuclear weapons in the Marshall Islands. In 1956, the Atomic Energy Commission regarded the Marshall Islands as "by far the most contaminated place in the world". The islands are impoverished, and one island Ebeye, holds the distinction of being the most densely populated place on earth.
