Altona is a town in Clinton County, New York, United States. The population was 2,887 at the 2010 census. The town was named after the Altona, Hamburg, district of Germany. The town contains a hamlet also called Altona.The town is located in north-central Clinton County. The western part is inside the Adirondack Park boundary, but the entire town is specifically excluded from the park by statute. Altona is northwest of Plattsburgh.