Over-the-Rhine, often abbreviated as OTR, is a residential neighborhood located in the urban basin of Cincinnati, Ohio. Over-the-Rhine is among the largest, most intact urban historic districts in the United States. Originally settled by German immigrants, the neighborhood became home to significant African-American and Appalachian populations during t…Over-the-Rhine, often abbreviated as OTR, is a residential neighborhood located in the urban basin of Cincinnati, Ohio. Over-the-Rhine is among the largest, most intact urban historic districts in the United States. Originally settled by German immigrants, the neighborhood became home to significant African-American and Appalachian populations during the mid-20th century. It is home to several of Cincinnati's most famous landmarks, including Music Hall and Findlay Market.