The Montgomery Bell Tunnel, also known as the Pattison Forge Tunnel, which Bell called "Pattison Forge" after his mother's maiden name, is a historic water diversion tunnel in Harpeth River State Park in Cheatham County, Tennessee. Built in 1819, the 290-foot (88 m) long tunnel is believed to be the first full-size tunnel built in the United States, and is the first used to divert water for industrial purposes. It was designated a Historic Civil Engineering Landmark in 1981, and a National Historic Landmark in 1994.
