The Marshall Islands, named after a British sea captain who explored the group in 1788, are scattered like flung necklaces over about 750,000 square miles of Pacific Ocean. Positioned 2,200 miles southwest of Hawaii, they occupy an area between four and 20 degrees north of the equator. The islands are aligned in two groups. Those to the west are the Ralik Chain; to the east, they're in the Ratak Chain. Altogether they total 34 islands and 850 sea-washed reefs.