Heidelberg castle: The architectural highlight of the region's most beautiful castle is the Renaissance courtyard—harmonious, graceful, and ornate.
Neckar Bridge: After a walk under the twin towers that were part of medieval Heidelberg's fortifications, you have the best view of the city and the castle.
Hornberg castle: With its oldest parts dating from the 12th century, this is one of the best of more than a dozen castles between Heidelberg and Stuttgart.
Stuttgart's Mercedes-Benz Museum: The history of the auto mobil is illustrated by 160 classic cars, from posh limousines to sleek racing cars.
Tübingen Altstadt: With its half-timber houses, winding alleyways, and hilltop setting overlooking the Neckar, Tübingen is the quintessential German experience.