Best SEO and internet marketing services in Clinton County NY. Clinton County zip codes - 12901, 12903, 12910, 12911, 12918, 12919, 12921, 12923, 12924, 12929, 12933, 12934, 12935, 12952, 12955, 12958, 12959, 12962, 12972, 12978, 12979, 12981, 12985, 12992 Clinton County is a county in the U.S. state of New York. It is situated in the north-east of the New York state. The county is named after George Clinton, the Governor of New York. Clinton County was founded in 1788. Plattsburgh is the county’s seat. According to the census in 2010 more than 82,000 people live there. 94% of residents speak English as their first and native language, 2,8% French and 1,7% Spanish. The county has the area of 1,118 square miles (2,900 km2), where 1,038 square miles is land and 80 square miles is water. Lake Champlain is situated in the east of the county. The Ausable River flows in the south. Beautiful Adirondack Park is located in the south-west of the Clinton County. Plattsburgh State University is located in the city of Plattsburgh and was founded in 1889, opened in 1890. Clinton Correctional Facility is a New York State Department of Correctional Services state prison for men and it is located in the village of Dannemora. Three airports are situated in the county: Plattsburgh International Airport, Clinton County Airport and Rouses Point Seaplane Base. Plattsburgh is the only city in the county. There are also several towns, villages and hamlets.