The Taconic Mountains and the Berkshire Mountains ranges of the Appalachian Mountains run through Fairfield County. The Taconics begin roughly in Ridgefield and the Berkshires begin roughly in Northern Trumbull, both running north to Litchfield County and beyond. A portion of the Taconics also is in rural Greenwich and rural North Stamford in Fairfield County and run north into Westchester County, New York, eventually re-entering Fairfield County in Ridgefield. A small portion of the Appalachian Trail runs through Fairfield County; the trail enters Connecticut in the northernmost and least populous town in the county, Sherman, and moves east into Litchfield County, which encompasses the majority of the Appalachian Trail in Connecticut.