7 Best Sights in Tübingen, Heidelberg and the Neckar Valley

The majestic silhouette of this massive castle is visible from miles away. The Hohenzollern House of Prussia was the most powerful family in German history. It lost its throne when Kaiser William II abdicated after Germany's defeat in World War I. The Swabian branch of the family owns one-third of the castle, the Prussian branch two-thirds. Today's neo-Gothic structure, perched high on a conical wooded hill, is a successor of a castle dating from the 11th century. On the fascinating 45-minute castle tour you'll see the Prussian royal crown and beautiful period rooms, all opulent from floor to ceiling, with such playful details as door handles carved to resemble peacocks and dogs. The restaurant on the castle grounds, Café Restaurant Burg Hohenzollern, offers choices from vegan up to rump steak along with pastries from  the local confectioner,  and there's an outdoor beer garden in season. From the parking lot it's a 20-minute walk to the castle entrance; a shuttle bus is now included in the admission price, and there are English-language tours on request (or you can download the new free self-guided app). While it's better to buy a ticket in advance to ensure entry, you can buy one at the carpark for an additional €3 if they are available for the day.

A wealth of vintage toys, model trains, and vehicles, including motorcycles, awaits children of all ages. This private collection, open to the public, includes Porsche, Ferrari, and Maserati race cars, an original 1957 VW Beetle, and a rare 1954 Lloyd. Ask a docent to start up the HO trains or one of the antique musical toys. Kids can ride one of the old pedal cars. There's also a small café and free parking.

An art gallery north of the Neckar, the Kunsthalle has become a leading local exhibition venue and generates a special kind of "art tourism," making it difficult to find local lodging if a popular exhibition is shown.

Houses of prominent burghers of centuries gone by surround this square, which is the heart of the Altstadt (Old Town), busy with open-air cafes in warm weather. At the open-air market on Monday, Wednesday, Friday, and Saturday from 7 to 5 in the summer and 9 to 3 in winter, you can buy flowers, bread, pastries, poultry, sausage, and cheese.

Begun in 1433, this building slowly expanded over the next 150 years, and served from around 1471 to 1805 as the seat of the court of Württemberg. Its ornate Renaissance facade is bright with colorful murals and a marvelous astronomical clock dating from 1511. The half-timber halls and reception rooms are adorned with paintings from the late 19th century.

The original castle of the counts of Tübingen (1078) was significantly enlarged and altered by Duke Ulrich during the 16th century. Particularly noteworthy is the elaborate Renaissance portal patterned after a Roman triumphal arch. The coat of arms of the duchy of Württemberg depicted in the center is framed by the emblems of various orders, including the Order of the Garter. Today the castle's main attraction is its magnificent view over the river and town and—of course—its extensive collection of artifacts from ancient cultures, including Ice Age and Egyptian art. The astronomy observatory, dating from the early 1800s, has been restored and re-opened to visitors. Be sure to check out one of the world's largest and best-preserved wine casks, which dates from 1549 and can hold 23,000 gallons. The Schloss is a 90-minute walk from Schlossbergstrasse, over the Spitzberg, or via the Kapitänsweg that ends north of the castle. Alternatively, you can take the 916 bus from downtown (€2–€4, 44 min.).

The late-Gothic church has been well preserved; its original features include the stained-glass windows, the choir stalls, the ornate baptismal font, and the elaborate stone pulpit. The windows are famous for their colors and were much admired by Goethe. The dukes of Württemberg, from the 15th through the 17th century, are interred in the choir.