Trenton is a city in northeastern Butler County, Ohio, United States, west of Middletown. The population was 13,021 at the 2020 census. It is part of the Cincinnati metropolitan area.

State Route 73 is an east–west state highway in the southern portion of the U.S. state of Ohio. Its western terminus is on U.S. Route 27 in Oxford at the intersection of SR 732. SR 73's eastern termin