The New Student's Reference Work/Neckar

Neck′ar, a river in Germany, flowing through Württemberg and Baden; it is one of the largest tributaries of the Rhine, rises on the eastern slope of the Black Forest, and pursues a winding course for 250 miles until it enters the Rhine at Mannheim.  It is navigable for about half its lower length.  Tübingen, Heidelberg, Heilbronn and Cannstatt are on its banks.