Plattsburgh (Mohawk: Tsi ietsénhtha) is a city in, and the chair of, Clinton County, New York, United States, situated on the north-western shore of Lake Champlain. The population was 19,841 at the 2020 census. The population of the surrounding (and separately incorporated) Town of Plattsburgh was 11,886 as of the 2020 census, making the mass population for anything of greater Plattsburgh to be 31,727. Plattsburgh lies just to the northeast of Adirondack Park, immediately outdoor of the park boundaries. It is the second largest community in the North Country region (after Watertown), and serves as the main personal ad hub for the sparsely populated northern Adirondack Mountains. The land approaching what is referred to as Plattsburgh was back inhabited by the Iroquois, Western Abenaki, Mohican and Mohawk people. Samuel de Champlain was the first ever recorded European that sailed into Champlain Valley and forward-thinking claimed the region as a ration of New France in 1609.

Plattsburgh was the site of the amphibious Battle of Plattsburgh in the War of 1812, a key American victory that marked the grow less of hostilities in the Northern United States. It has been an important military outpost for much of its history, from hosting one of the largest Citizens’ Military Training Camps prior to World War I, and Plattsburgh Air Force Base, the east coast middle of operations for the Strategic Air Command during much of the Cold War period. The conversion of the base to a civilian airstrip in the 1990s resulted from the Base Realignment and Closure process during the wind by the side of of the Cold War, and today it serves as a hub for economic further for the region. The city was named one of the Financial Times Top 10 Micro City of the Future several times.^[when?]

The city of Plattsburgh is the population center and county chair at the heart of the Plattsburgh micropolitan statistical area (MSA) with a population of 82,128 according to the 2010 Census. A statistical area representing the greater Plattsburgh region (as defined by the U.S. government), the Plattsburgh MSA includes whatever communities in the terse Clinton County area.

Plattsburgh was founded by Zephaniah Platt in 1785 after he was arranged the home by George Clinton. Platt, who was from Poughkeepsie, New York, established the extra city of Plattsburgh to buffer emerging American interests in the Saint Lawrence River valley and Lake Champlain valley after the American victory in the American Revolutionary War. The centralized American authority proclaimed Plattsburgh in 1785.