For centuries, native Eskimos cut blocks of oil-soaked tundra from natural seeps to use as fuel. In the 1920s, explorers arrived and began poking holes. In 1968, they discovered Prudhoe Bay State No. 1, the largest oil field in North America and one of the largest in the world, and a year later the adjacent Kuparuk field, the second-largest.
— Jeanne Marie Laskas