Saint Croix:1 River, 75 mi (121 km) long, rising in the Chiputneticook Lakes and flowing SE to Passamaquoddy Bay, forming part of the U.S.-Canada border; navigable to Calais, Maine. The river is used for power and to float logs downstream. In 1604, French explorer Samuel de Champlain helped establish a colony on St. Croix (Dochet) Island (now an international historic site) near the river's mouth; it was abandoned in 1605. 2 River, 164 mi (264 km) long, rising in the lake district of NW Wis. and flowing generally S to the Mississippi River at Prescott, Wis.; forms part of the Wis.–Minn. line. The Dalles, a scenic gorge, is located in Interstate Park. A hydroelectric plant at St. Croix Falls supplies power to the Minneapolis–St. Paul metropolitan area.

Saint Croix (sānt kroi), island (2010 pop. 50,601), 80 sq mi (207 sq km), the largest of the U.S. Virgin Islands, in the West Indies. Christiansted, on the northeast coast, is the island's leading town. A campus of the Univ. of the Virgin Islands is located at Golden Grove, midway between Christiansted and Frederiksted. Buck Island Reef National Monument is off the island's NE coast.