- Established: 1809
- Population: 73,966 (2000 census)
- County Seat: Monticello
- Tourism Region: The Catskills
- Information: Sullivan County website
- Bordering Counties: Delaware, Orange, Ulster, Pike Pa., Wayne Pa.
- Area code: 845
- Origin of Name: In honor of Major General John Sullivan, who was a hero
in the American Revolutionary War.
- Incorporated Cities: none
- Villages: Bloomingburgh, Jeffersonville, Liberty, Monticello,
- Towns: Bethel, Callicoon, Cochecton, Delaware, Fallsburgh, Forestburgh,
Fremont, Highland, Liberty, Lumberland, Mamakating, Neversink, Rockland,