Hawaii is surrounded on all sides by the Pacific Ocean. The 50th state of the United States is a chain of islands located in the Central Pacific.
Hawaii is the northernmost chain of islands in Polynesia, an oceanic subregion. Thousands of islands, or archipelagos, are scattered in chains throughout the Pacific. Hawaii is about 2,000 miles southwest of the North American mainland. Its coastline is the fourth largest in the United States, at about 750 miles. The Hawaiian islands were formed by a "hotspot" of magma below the earth's crust creating underwater mountains, which grew above sea level over time. Plate tectonics caused the formations to move away from the hotspot, which accounts for the geographical shape of the island chain.