Fort Drum is a U.S. Army military reservation and a census-designated place (CDP) in Jefferson County, near the western border of northern New York, United States. The population of the CDP portion of the base was 12,955 at the 2010 census. It is home to the 10th Mountain Division.

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.