New Hampshire, constituent state of the United States of America. One of the 13 original U.S. states, it is located in New England at the extreme northeastern corner of the country. It is bounded to the north by the Canadian province of Quebec, to the east by Maine and a 16-mile (25-km) stretch of the Atlantic Ocean, to the south by Massachusetts, and to the west by Vermont. The capital is Concord, located in the south-central part of the state.