county, northwestern New York state, U.S., located in a lowland region with several swamps, midway between Buffalo and Rochester. It is drained by Tonawanda, Oak Orchard, and Oatka creeks. The major forest types are oak and hickory. Public lands include Iroquois National Wildlife Refuge and Darien Lakes State Park; Tonawanda Indian Reservation is in the northwestern corner of the county.
Learn more about Genesee with a free trial on Britannica.com.