Star Grange No. 9

District School No. 19 is a historic one-room school building located at Hounsfield in Jefferson County, New York. It is a one-story, rectangular one room structure built about 1837 of rubble Chaumont limestone. It was last used as a school in 1938.It was listed on the National Register of Historic Places in 1989.

Sulphur Springs Cemetery is a historic rural cemetery located at Hounsfield in Jefferson County, New York. It is a cemetery that includes both the original burial ground dating to about 1800 and the much larger "romantic landscape" expansion dating to about 1879. The earliest extant stones date from 1812.It was listed in the National Register of Historic Places in 1989.

Ressequie Farm is a historic farm complex located at Hounsfield in Jefferson County, New York. The farm complex consists of a 1+1⁄2-story gabled ell, L-shaped farmhouse built about 1840 in the Greek Revival style and five outbuildings. Contributing outbuildings are a cattle barn, granary, pig house, chicken coop, and former carriage house.It was listed on the National Register of Historic Places in 1989.

Stephen Simmons House is a historic home located at Hounsfield in Jefferson County, New York. The farmhouse was built about 1818 and consists of a 2+1⁄2-story main block and an original 1-story rear wing, with a modern 1-story wood-frame garage attached to the wing. The walls are of roughly dressed local ashlar limestone laid in even courses and trimmed with smoothly dressed limestone.It was listed on the National Register of Historic Places in 1989.

East Hounsfield Christian Church is a historic church located at Hounsfield in Jefferson County, New York, United States. It was built about 1844 and is a two-story, three bay wide and three bay deep, gable front frame structure with Greek Revival features. A one-story wood frame wing is attached to the rear by a small hyphen. The front features a two-stage wood belfry.It was listed on the National Register of Historic Places in 1989.

Hounsfield is a town in Jefferson County, New York, United States. The population was 3,466 at the 2010 census. The name of the town is from Ezra Hounsfield, a land agent and land owner. He once owned the Southern part of the township. The town was named by Augustus Sacket. Hounsfield is in the western part of the county and is west of Watertown.

Watertown International Airport (IATA: ART, ICAO: KART, FAA LID: ART) is in the Town of Hounsfield in Jefferson County, New York, United States, 6 mi (5.2 nmi; 9.7 km) west of Watertown. The airport is used for general aviation, but has scheduled passenger service subsidized by the Essential Air Service program. The airport has no scheduled international passenger flights, but is available as an international port of entry for private aircraft on two hours' advance notice from pilots. The Federal Aviation Administration says this airport had 2,203 passenger boardings (enplanements) in calendar year 2010, 4,449 in 2011, and 16,988 in 2012. It is included in the Federal Aviation Administration (FAA) National Plan of Integrated Airport Systems for 2023–2027, in which it is categorized as a non-hub primary commercial service facility.

Jefferson County is a county on the northern border of the U.S. state of New York. As of the 2020 census, the population was 116,721. Its county seat is Watertown. The county is named after Thomas Jefferson, third President of the United States of America. It is adjacent to Lake Ontario, southeast from the Canada–US border of Ontario. The county is part of the North Country region of the state. Jefferson County comprises the Watertown-Fort Drum, NY Metropolitan Statistical Area. The popularity of the area as a summer tourist destination results in a dramatic increase of population during that season. In 2014, it elected Colleen M. O'Neill as the first woman county sheriff in the state. She had served with the New York State Police for 32 years. The United States Army's 10th Mountain Division is based at Fort Drum. The base had a total population of nearly 13,000 according to the 2010 census.

Conklin Farm is a historic farm complex located at Hounsfield in Jefferson County, New York. The farm complex consists of a 2+1⁄2-story gable-front double-farmhouse, horse barn, milk house, and garage. Also on the property are the ruins of a cow barn with attached silo and the ruins of a chicken coop.It was listed on the National Register of Historic Places in 1989.

Adams Center (formerly called Adams Five Corners) is a hamlet and census-designated place (CDP) in the town of Adams in Jefferson County, New York, United States. The population was 1,492 during the 2020 decennial census.

Dr. Samuel Guthrie House is a historic home located at Hounsfield in Jefferson County, New York. The home comprises a rectangular two-story, five-by-two-bay, brick Federal style core building and a rectangular one-story rear wing. The rear wing is in three sections: a section constructed around 1822, an addition from the early 20th century, and a third from about 1910. It was listed on the National Register of Historic Places in 1989.

Dexter Marsh is a 1,350-acre (5.5 km2) marsh located at the eastern end of Lake Ontario in Dexter, New York. It was declared a National Natural Landmark in May 1973. The marsh is managed by the New York State Department of Environmental Conservation as the Dexter Marsh Wildlife Management Area. The marsh is a popular fishing and trapping area as well as a migratory bird layover. Lacking barrier beaches, it is directly exposed to Lake Ontario's winds and waves. It is a relatively undeveloped bay-head area on the Great Lakes.