State Route 3 (SR 3) is a major north–south (physically northeast-southwest) highway in Ohio which leads from Cincinnati to Cleveland by way of Columbus.

[2] It is the only state route to enter all three of Ohio's largest cities, though it has largely been bypassed by Interstate 71 (I-71).

From there, SR 3 continues solo to Sunbury, where it joins US 36 for just over 24 miles (39 km) until it reaches Mount Vernon.

SR 3 ends in Cleveland at Public Square, with the last several miles concurrent with US 42 from Parma.

It is one of nine other routes to enter downtown Cleveland at Public Square.