Massachusetts, part of the northeastern conglomeration of states known as "New England," is surrounded by New Hampshire and Vermont to the North, New York to the west, Rhode Island and Connecticut to the south, and only the Atlantic Ocean on the east. Massachusetts is called "the Bay State" because of the large bays that create its coastline: Massachusetts Bay, Cape Cod Bay, Buzzards Bay, and Narragansett Bay. The peninsula Cap Cod also helps create the unique coastline of Massachusetts; it's a large, arm-shaped peninsula on the southeast corner of the state. Martha's Vineyard and Nantucket are islands to the south of Cape Cod.
Charles River is Massachusetts's longest river contained entirely within the state, and at its mouth lays Boston - the state's largest city, with a population of almost 6 million people in the metropolitan area (though most of those people live in the highly populated suburban area, not the city). The Commonwealth of Massachusetts is made up of 14 counties - Barnstable, Berkshire, Bristol, Dukes, Essex, Franklin, Hampden, Hampshire, Middlesex, Nantucket, Norfolk, Plymouth, Suffolk, and Worcester. Within these counties are 50 cities and 301 towns. Four of the most prominent areas of Massachusetts are Western Massachusetts, Boston, Martha's Vineyard, Nantucket, and Cape Cod.