State Route 174 (SR 174) is a 9.56-mile (15.39 km) long north–south state highway in the northeastern quadrant of the U.S. state of Ohio. The highway runs from its southern terminus at a T-intersection with Old Mill Road in a quiet residential neighborhood in the eastern Cleveland suburb of Gates Mills to its northern terminus at a signalized intersection with U.S. Route 20 (US 20) in Willoughby that doubles as the eastern terminus of SR 640.

Lake County is a county in the U.S. state of Ohio. As of the 2020 census, the population was 232,603. Its county seat is Painesville, and its largest city is Mentor.