Ulster County is a county in the U.S. state of New York. It is situated along the Hudson River. As of the 2020 census, the population was 181,851. The county seat is Kingston. The county is named after the Irish province of Ulster. The county is part of the Hudson Valley region of the state.

Otsego County is a county in the U.S. state of New York located within the Mohawk Valley Region. As of the 2020 census, the population was 58,524. The county seat is Cooperstown. The county's population center is Oneonta. The name Otsego is from a Mohawk or Oneida word meaning "place of the rock." The county is part of the Mohawk Valley region of the state.