Orange County is in southeastern New York State, directly north of the New Jersey-New York border, west of the Hudson River, east of the Delaware River and northwest of New York City. It borders the New York counties of Dutchess, Putnam, Rockland, Sullivan, Ulster, and Westchester, as well as Passaic and Sussex counties in New Jersey and Pike County in Pennsylvania.
Orange County is the only county in New York State which borders both the Hudson and Delaware Rivers.
Orange County is where the Great Valley of the Appalachians finally opens up and ends. The western corner is set off by the Shawangunk Ridge. The area along the Rockland County border (within Harriman and Bear Mountain state parks) and south of Newburgh is part of the Hudson Highlands. The land in between is the valley of the Wallkill River. In the southern portion of the county, the Wallkill valley expands into a wide glacial lake bed known as the Black Dirt Region for its fertility.