1960
The Volkswagen Beetle, which was built from 1938 to 2003, is the most famous Volkswagen, the most famous German car, and generally one of the most famous cars ever. Until 1967 it was called Type 1, 1200, 1300 (after the engine capacity in cc), but popularly it was called beetle because of its shape, after which the manufacturer started using that name itself. More than 20 million units of the Volkswagen Beetle were produced from 1937 to 2003. This makes it the longest and the most produced car on the same platform.
[source: Wikipedia]