Peekskill is a city in northwestern Westchester County, New York, United States, 35 miles (56 km) north of New York City. Established as a village in 1816, it was incorporated as a city in 1940. It lies on a bay along the east side of the Hudson River, across from Jones Point in Rockland County. The population was 25,431 at the 2020 U.S. census, up from 23,583 at the 2010 census. It is the third-largest municipality in northern Westchester County, after Cortlandt and Yorktown.

Westchester County is located in the U.S. state of New York. It is the seventh most populous county in the State of New York and the most populous north of New York City. According to the 2020 United States Census, the county had a population of 1,004,456, its highest decennial count ever and an increase of 55,344 (5.8%) from the 949,113 counted in 2010. Westchester covers an area of 450 square miles (1,200 km2), consisting of six cities, 19 towns, and 23 villages. Established in 1683, Westchester was named after the city of Chester, England. The county seat is the city of White Plains, while the most populous municipality in the county is the city of Yonkers, with 211,569 residents per the 2020 census. The county is part of the Hudson Valley region of the state.