Main Industries: Suffolk County is home to the scientific innovations at Brookhaven National Lab, Stony Brook University and the high-tech Route 110 corridor. Traditional family farms and wineries in Suffolk County's rural East End make it the biggest agricultural county in New York State. Land: Suffolk County occupies the central and eastern part of Long Island, in the extreme southeast of New York State. The eastern end of the county splits into two peninsulas, known as the North Fork and the South Fork.