Interstate 275 (Ohio–Indiana–Kentucky)

Interstate 275 (I-275) is an 83.71-mile-long (134.72 km) highway in Ohio, Indiana, and Kentucky that forms a complete beltway around the Cincinnati metropolitan area and includes a part in a state (Indiana) not entered by the parent route. It had been the only auxiliary Interstate that enters three states, but that changed in July 2018 when I-295 in Delaware and New Jersey was extended into Pennsylvania. It is the longest beltway with an Interstate highway designation in the United States, enclosing an area of over 250,000 acres (100,000 ha). It is also the third longest beltway overall in the United States—only the Sam Houston Tollway and the Grand Parkway encircling Greater Houston are longer. For a short distance in northwest Hamilton County, it overlaps with I-74 and US Route 52 (US 52).

I-275 is also known as the Cincinnati Bypass and officially known as the Donald H. Rolf Circle Freeway in Ohio, after a state senator, but locals rarely use these names, instead simply referring to it as "275" or "the loop". In 2011, Kentucky named its segment the Ronald Reagan Highway, not to be confused with Ronald Reagan Cross County Highway across the river in Cincinnati. The section in Clermont County is also designated as the Staff Sergeant Matt Maupin Veterans Memorial Highway.