The Hudson Valley refers to the canyon of the Hudson River and its adjacent communities in New York State, generally from northern Westchester County northward to the cities of Albany and Troy. Historically a cradle of European settlement in the northeastern United States and a strategic battleground in colonial wars, it now consists of suburbs of the metropolitan area of New York City at its southern end, shading into rural territory, including "exurbs," farther north.

Geographically, the Hudson Valley could refer to all areas along the Hudson River, including Bergen County, New Jersey. However, this definition is not commonly used and the Tappan Zee Bridge is often considered the southern limit of the area. Though Westchester County is often classified as part of the region, Westchester residents who live at the southern end of the county (and especially the parts closer to the Long Island Sound than the Hudson River) generally do not associate themselves with the region. Including all of Westchester County in the definition of the region would seem unusual to many and seem like something one might only read in a travel guide. In fact, there is a road sign on the New York State Thruway in Yonkers that suggests that the "Hudson Valley region" is located somewhere further to the north and west along the Thruway.