The Hudson River Historic District, also known as Hudson River Heritage Historic District, is the largest such district on the mainland of the contiguous United States. It covers an area of 22,205 acres (34.6 square miles, 89 km²) extending inland roughly a mile (1.6 km) from the east bank of the Hudson River between Staatsburg and Germantown in Dutchess and Columbia counties in the U.S. state of New York. This area includes the riverfront sections of the towns of Clermont, Red Hook, Rhinebeck and part of Hyde Park. This strip includes in their entirety the hamlets of Annandale, Barrytown, Rhinecliff and the village of Tivoli. Bard College and two protected areas, Margaret Lewis Norrie State Park and Tivoli Bays Unique Area, are also within the district.