The Danube, celebrated in art and song, might be the world's most feted river. (After all, is there anyone who can't hum a few bars of the "Blue Danube Waltz"?) Meandering southeast from its origins in Germany's Black Forest, the Danube isn't Europe's longest river -- the Volga takes that honor. But, on its 1,775-mile course to the Black Sea, it flows through, or borders, 10 countries -- more than any other river in the world.
Along the way it shadows centuries-old storybook villages that appear unchanged by time and cuts through sophisticated world capitals, like Vienna and Budapest. Viking River Cruises' three most popular Danube River itineraries range from a 15-day Grand European Tour from Amsterdam to Budapest to two eight-day sailings, one from Passau, Germany, to Budapest, and the other from Budapest to Nuremberg, Germany.
Overview: Due to its location 100 miles north of Munich's airport, Bavaria's second-largest city is a popular starting and ending points for many Danube cruises. Nuremberg's name may be synonymous with the trials that brought German war criminals to justice, but there's more to this city than its courthouse.
Don't miss: Nuremberg Castle, home to emperors and kings from 1050 to the 1500s. From the castle, which dominates the historic center, stroll past half-timbered houses to Market Square, one of Germany's most beautiful. The sprawling National Germanic Museum, with its mix of architectural styles, originally was housed in a 14th-century monastery. It's since been expanded with neo-Gothic and contemporary styles to accommodate the museum's expanding collection. Its entrance is on the Way of Human Rights, a streetscape art installation dedicated to peace.
Independent Meanderings: World War II buffs will have plenty to see, including the former Nazi Party Rally Grounds and Courtroom 600 in the Palace of Justice, site of the Nazi war trials.
Hidden gem: For a peek at a literal hiding place, visit the "art bunkers" -- medieval beer cellars where priceless artwork was stashed for safekeeping during the war. Afterward, view some of those works in St. Sebaldus Church by the old city hall.
Active Pursuits: Many of Nuremberg's 14th- and15th-century city walls remain. Follow a 3-mile path to view the ancient gates and towers.
Insider tip: Don't leave town without sampling a Nuremberg sausage -- or three. They're spiced with mace, pepper and marjoram and weigh less than an ounce. To order like a local, ask for Drei im Weggla -- three in a bun. Try them at the uber-Bavarian Behringer's Bratwurstglocklein (Waffenhof 5). Yes, it's touristy, but it's historic, too. After all, artist Albrecht Durer, one of Nuremberg's most famous sons, dined here in the 1500s.
Overview: The city's well-preserved Old Town, spared the extensive war damage that ravaged much of Germany, is now a UNESCO World Heritage site.
Don't miss: The imposing Old Town Hall that dates from the 14th to 18th centuries. Inside are historical apartments, art collections and other antiquities. And, check out the still-in-use 12th-century Old Stone Bridge and the Gothic twin-spired Regensburg Cathedral nearby.
Independent Meanderings: Regensburg is the best town for boutique shopping on the itinerary. Just wander freely....
Hidden gem: With five breweries, plus myriad smaller producers, Regensburg is nirvana for beer-lovers. Explore on your own, or take an optional guided tour with stops at the Ratskeller and the Weissbrauhaus for a primer on local beers, which run the gamut from wheat beers and pilsners to dark brews. We love the biergarten (beer garden) in the courtyard of the Hotel Bischofshof am Dom.
Active Pursuits: Take a power walk through the lovely, 4-acre riverside Herzogspark. The 13th-century spot has curated gardens and showcases the remains of the town's former moat.
Insider tip: Regensburg's Old Town can be congested in peak summer months, but Stadtamhof, a historic district on a small island in the river, is relatively tranquil. Visit the Andreasstadel, a former warehouse that now houses artists' studios and a cafe. Take home a jar of Wurstkuchl sweet mustard from the Historische Wurstkuchl (Historic Sausage Kitchen), a riverfront eatery that has been serving satisfied diners since 1135.
Overview: Dubbed the Venice of Bavaria, because of its location at the confluence of the Danube, Inn and Ilz rivers, this compact medieval city with two castles and a mountaintop monastery, packs a delightful punch. Napoleon declared it Germany's most beautiful burg. You'll be a fan, too.
Don't miss: A stroll along Old Town's narrow, cobbled lanes chockablock with confection-colored buildings from the 15th to 18th centuries. Shops selling Bavarian dirndls and lederhosen abut art galleries showcasing edgier fare. Take in an organ concert at the over-the-top ornate St. Stephen's Cathedral Monday–Saturday from May to October. The cathedral pulls out all the stops in its Baroque flourishes, and so do the musicians at the keyboard of Europe's largest pipe organ. It's a feast for the eyes and the ears.
Independent Meanderings: Enjoy the views -- and work off the strudel -- with a panoramic tour starting from the hilltop Mariahilf Monastery on the city's south side, through Old Town and along the Inn River, and then across the Danube and into the northside hills, site of Veste Oberhaus. The grand fortress complex dates to the 13th century.
Hidden gem: The 321-step pilgrimage staircase at the Mariahilf Monastery sports - covered passageway adorned with hundreds of folk-art depictions made by true believers.
Active Pursuits: Hike the Passau hills or book a bike and ride the flat riverfront path.
Insider tip: Sample local gingerbread at Cafe Simon (Rindermarkt 10) on its flower-filled patio. In business since 1903, it makes the treat the old-fashioned way, with honey. Another sweet spot: Cafe Greindl (Witgasse 8) is a cheerful tearoom serving to-die-for cakes, strudels and more. (Get half off on some pastries after 5 p.m.) Dachshund-lovers will want to make a beeline for the Dachshund Museum (Grosse Messergasse 1), with a gift shop guaranteed to satisfy all your dachshund needs.
Austria's Linz and Salzburg -- and the Czech Republic's Cesky Krumlov
Overview: Austria's third-largest city sports a bustling Old Town lined with 400-year-old Baroque facades. And, although its Roman origins date to A.D. 799, the city is hardly stuck in the past. Check out its cutting-edge architecture, including the riverfront Lentos Art Museum, which pulses with exterior colored lights at night. Even its 17th-century hilltop castle, now an expansive cultural history museum, has a contemporary glass and steel wing. That said, Linz honors its history. Watch for plaques in Old Town marking notable sites, such as where composers Wolfgang Mozart slept and Anton Bruckner studied.
This is a power-touring day on a Danube River cruise. In addition to its own appeal, Linz is a jumping-off port for day trips to places like Austria's Salzburg and the Czech Republic's Cesky Krumlov. It can be tough to pick just one!
Don't miss: Cesky Krumlov Castle located in the Czech Republic city of the same name. It's a full-day jaunt from Linz, but the castle and the town's well-preserved historic center are worth the trip, which is an included Viking tour. Another popular full-day tour from Linz is a day trip to Salzburg, Austria. (Cue "The Sound of Music" soundtrack.)
Independent Meanderings: Sinnesrauch -- roughly translated "sensory intoxication" -- is a seasonal art happening from late May to mid-October. It consists of a circuit of walkways, bridges and stairs studded with large-scale interactive exhibits. Bonus: a bird's-eye view of Linz.
Hidden gem: In Linz: Though you can't really call the futuristic Ars Electronica Center "hidden" -- especially at night when it's illuminated by 40,000 LED lights -- it is a gem. Situated on the north bank of the Danube across the bridge from where the ships dock, this cutting-edge venue poses serious questions like, "How do machines think?" And, yes, it'll make you think. But, mostly it's just fun, with interactive virtual reality displays and a mind-bending Deep Space 8K theater. Sounds fab.
Active Pursuits: In Cesky Krumlov, climbing the oft-steep steps of the castle's towers, offers an amazing view. You'll have earned a beer by the time you climb back down again!
Insider tip: Sample the city's namesake confection, the Linzer torte, a latticed-topped jam-filled pastry. The 400-year-old recipe claims fame as the world's first cake. That's because Linz's early history as a trade hub gave bakers access to necessary ingredients, such as spices from Asia. Sample the Linzer torte at Cafe Traxlmeyr (Promenade 16), a Viennese-style coffeehouse since 1847, or Konditorei Jindrak (Herrenstrasse 22). For a contemporary take on tradition, try Hofbackerei 2.0 (Hofgasse 3).
Overview: Melk sits at the point where the Danube flows through the Wachau Valley, a stretch that boasts some of the most gorgeous terrain on the entire river. Its small, but well-preserved Old Town is fun to explore. Check out the Rathausplatz (Town Hall Square), with its 17th-century House for Itinerates and old city hall. Part of the ancient town wall is visible on Kremser Strasse. And, a local museum is now installed in the 1792 post office.
Don't miss: Melk Abbey. The magnificent Benedictine abbey is on a hill overlooking town and was originally built in the 11th century. Several fires ravaged the original structures and what has been rebuilt is in the Baroque style. Give yourself plenty of time to explore. The imposing structure includes a Marble Hall with ornately painted ceiling, a voluminous library housing rare manuscripts, a double-spired abbey church and Baroque gardens.
Independent Meanderings: Melk, aside from its abbey, is one of the least touristic towns on the Danube. Sync up with locals by poking into butcher shops and bakeries.
Hidden gem: Schallaburg Castle lies a few miles south of Melk. You'll know you've reached the 900-year-old Renaissance beauty when you see two almost 100-foot-long stone dragons at the entrance.
Active Pursuit: Take a stroll or bike ride on the Donauradweg cycling path that follows the Danube. (But, take care; it's a popular path.) The 24-mile stretch between Melk and Krems cuts through apricot orchards and vineyards, and within feet of well-manicured yards.
Insider tip: The Roter Faden (Red Thread) marks a third-of-a-mile route leading to Melk's key sites. Borrow an audio guide from the tourist office to enhance your stroll.
Overview: The tiny town has long been on tourists' radar, thanks, in part, to being the spot where the English king Richard the Lionheart was imprisoned while returning from the Crusades circa 1192. But, even minus that historical note, the town's setting in the heart of the Wachau Valley renders it a must-see. So does its signature blue-and-white spired abbey church. It's a beautiful town but incredibly touristy. It's also amazingly compact, essentially one street long.
Don't miss: Durnstein Castle ruins. Richard the Lionheart was imprisoned here a year for not sharing his spoils of war. He was freed after ransom was paid. The castle was destroyed by the Swedes in 1645, but you can see a model of it at Durnstein Abbey.
Independent Meanderings: The town is pretty compact but the countryside beyond sprawls. Stroll through walking paths that cut through vineyards.
Hidden gem: Some local cellars worthy of a stop for a sip: Domane Wachau is a short (and stunningly beautiful walk outside of town, and is known for its reisling and gruner weltliner (and makes a fine rose). Another great spot right in town is Weingut FX Pichler at Oberloiben 57.
Active Pursuits: Climb to the castle ruins, about 30 minutes from town. The trail is rocky but well-marked, and you'll be rewarded with splendid views at the top.
Insider tip: Cycling is also a lot of fun here -- not just because of the towpath along the river but also because pathways have been created to let you walk or bike through the vineyards, too.
Overview: Entering Krems through the Steiner Tor, its 15th-century fortress-like gate, is like walking into a fairy tale. Krems and adjacent Stein mark the eastern end of the bucolic Wachau Valley. The spectacular wine-growing region has been deemed worthy of a UNESCO Cultural Landscape designation.
Don't miss: Gottweig Abbey, a hilltop Benedictine monastery, a short bus ride from town, and included as a standard Viking tour. Besides enjoying splendid views of the Wachau Valley, you'll learn about the abbey's 900-year history. It continues to be a working abbey, with 44 affiliated monks who lead a cloistered existence when not overseeing the agricultural and touristic interests that fund the operation. Fun fact: Prospective monks can apply via Facebook.
Independent Meanderings: A simple walk through Krems is delightful.
Hidden gem: The pedestrian-only main street, Obere Landstrasse, leads to a labyrinth of narrow alleys that meander up the hillside. Worth the climb is Fraue-Piaristen Church, a Gothic beauty completed in 1520. Even if the church doors are closed, the exterior frescos are worth the effort of getting there.
Active Pursuit: Sign up for an optional cycling tour via electric bike. Flat cycling trails follow the Danube to the charming village of Durnstein. Or, rent an electric bike (30 euros (about $35) a day at the city tourist office) and take off on an independent riverside jaunt.
Insider tip: Sample Marillenschnaps, the local apricot brandy, at Hellerschmid distillery (Obere Landstrasse 36), which also sells nonalcoholic fare like apricot jam. Get a free audio guide from the tourist office (add 2 euros (about $2) for headphones). The 18-euro (about $20) Supercombi ticket enables admission to most museums.
Overview: With its grand palaces, dramatic churches and broad boulevards, this elegant capital wows the senses. But, it can also overwhelm them. Happily, there are opportunities galore to pause and soak in the scene.
Don't miss: Schonbrunn Palace, the Hapsburg Dynasty's summer digs just outside the city. Guided tours include the imperial apartments and royal gardens. In central Vienna, Hofburg Palace, the royals' winter place, has a jaw-dropping 18 wings and 2,660 rooms. It now houses three museums. Other ways to take home a Viennese memory: attending a Mozart and Strauss concert featuring performers in period dress, a behind-the-scenes visit to the famed Lipizzaner stallions' stables and a traditional evening out at a local vineyard. Shop like a local on an optional outing accompanied by a Viking chef. Wander through a farmers market while sampling Austrian cheeses, fresh produce and more.
Independent Meanderings: Mix it up with locals at the Prater, a sprawling amusement park/green space. It's open March to October, but you can take in epic views from its giant Ferris wheel year-round.
Hidden gem: The Museum of Applied Arts (Stubenring 5) focuses on arts, crafts and design. After touring the galleries, retreat to the peaceful garden cafe out back to relax on the lawn with a cool drink. Another under-the-radar museum is the Hundertwasser, dedicated to Friedensreich Hundertwasser, one of Austria's most influential artists, whose mantra in his art and architecture can be explained as "a straight line is evil." Exhibits include paintings, tapestries and architectural elements created by this man of many talents.
Active Pursuits: To work off the calories, rent a bike from Citybike Vienna (Citybikewien.at) and hit the city's miles of bike lanes. Alternately, several outfitters, including Venture Vienna, offer small-group kayaking tours on the river for an up close and personal view of the waterway.
Insider tips: A number of historic churches, including St. Peter's, stage free or low-priced concerts on a regular basis. Another spot from which to drink in the view (and libations) of this classically beautiful city is the floor-to-ceiling-windowed Das Loft in the Sofitel Hotel. Stop for a melange (Viennese-style cappuccino) at a historic coffeehouse like local hangout Cafe Hawelka (Dorotheergasse 6) or the ornate Cafe Landtmann (Universitatsring 4), one of Sigmund Freud's favorite haunts. Refuel with a kasekrainer (a hot dog with cheese) from a ubiquitous Viennese sausage stand or savor the Sachertorte at Demel (Kohlmarkt 14).
Overview: The capital's small, but lovely 18th-century Old Town has shed the somber grays of the Communist era in favor of more optimistic pinks, blues and greens. There's no better way to experience this delightful spot than by simply wandering among its maze of pedestrian plazas. The towering green spire of Michael's Gate, the city's sole surviving medieval entrance, is a trusty landmark to keep you oriented. Even in the height of tourist season, Old Town feels less frenetic than those of some nearby capitals. It's well loved and well used by locals. As you stroll, be on the lookout for whimsical brass sculptures, such as the likeness of a hard-hatted worker peering out from a manhole cover.
Don't miss: Bratislava Castle. The reconstructed building houses exhibits about Slovakia's past. Go for the history lesson, or just the splendid views of Old Town and the Danube.
Independent Meanderings: Old Town is full of small souvenir shops. One that stands out: Obchod v Muzeu (translation: Shop in the Museum) at Biela 419/6. Here, you'll find locally made chocolates and other Slovak treats, plus regional crafts. Antique cabinetry, cash registers and other tools of the shopkeeper's trade are displayed in what is one of Bratislava's oldest retail establishments. Finally, stick to official bank ATMs to avoid excessive user fees.
Hidden gem: Grand Cru Wine Gallery (Zamonicka 404/8) offers generous pours of regional wines at reasonable prices in sleek surroundings.
Active Pursuit: BikeBratislava (BikeBratislava.sk) will put you on a bike or scooter and send you off into the countryside with a detailed itinerary.
Insider tip: It's possible to climb to the top of the city's landmark Michael's Tower, but the entrance can be tricky to locate. Look for a heavy wooden door to the right of Michael's Gate arch. The ticket office is inside.
Overview: If you're lucky, your ship will make a grand entrance after dark into one of Europe's most dramatic cities. Bridges across the Danube that link Buda, the hilly castle district, with Pest, the more commercial area, are illuminated by night, as are landmark buildings like the huge, neo-Gothic Parliament. It's pure magic. By day, wander the hills of Buda, site of the castle, Fisherman's Bastion and Matthias Cathedral. Pest has its charms, too. Just blocks from the Danube, the broad, pedestrian-only Vaci Street is lined with shops and eateries. Try kurtoskalacs ("chimney cakes") at Molnar's Kurtoskalacs (Vaci utca 31) and shop for hand-carved wooden boxes, embroidered textiles and other local handicrafts at stalls along the way.
Don't miss: The castle and surrounding Castle District in Buda. The ride up Castle Hill in a funicular is fun; the attractions on top are monumental and unforgettable. Key among them is the castle itself, a UNESCO World Heritage site constructed for more than seven centuries. While you're there, explore the imposing Fisherman's Bastion and lovely Matthias Cathedral.
Independent Meanderings: Look for Budapest Info Points, often located within retail establishments, for maps and other basic info. They sell the Budapest Card, which gives free access to 19 museums and other attractions, plus rides on public transportation and free walking tours. If you're spending time in Budapest before or after your cruise, it's a smart buy.
Hidden gem: While "gem" isn't an apt descriptor of the House of Terror (Andrassy utca 60), the place is a must-see for anyone interested in learning about the horrors wrought by the Nazi and Soviet occupations in the last century. On a lighter note, a delightful spot that's truly hidden is the Faust Wine Cellar beneath the Hilton Hotel in Buda. It's part of a network of caves and tunnels that run under Castle Hill.
Active Pursuits: Cycling, an optional Viking tour, is an ideal way to cover ground in this dynamic city. Most bike tours make a beeline for Margaret Island, Budapest's version of Central Park, in the middle of the Danube. On the way over, check out the view from the Margaret Bridge, which takes in the Parliament building on one side and Buda Castle and Matthias Church on the other. Margaret Island aims to please a varied audience. Among the diversions: a zoo, a Japanese garden, a fountain choreographed to music and even an Olympic-size swimming pool.
Insider tip: Have a leisurely soak in a one of the city's lavish thermal baths. A tradition dating to Roman times, Budapest bathhouse culture continues to thrive. Among the most iconic spots: Gellert Thermal Bath (Kelenhegyi utca 4), Szechenyi Medicinal Bath (Allatkerti krt 9-11) and Rudas Baths (Dobrentei ter 9). Coffee culture is another of Budapest's signature attributes. Take a seat at a cafe on Budapest's grandest boulevard, Andrassy Avenue, and watch the passing parade. Classic and clubby Muvesz Kavehaz (Andrassy utca 29) has been in business since 1898. In the Castle District, Pest-Buda Bistro (Fortuna utca 3) sports an outdoor terrace overlooking a central square. Or, dig into something sweet with your cuppa at the city's oldest, Ruszwurm (Szentharomsag utca 7).
Jayne Clark is a former staff travel reporter at USA Today. She lives in Washington, D.C.
Want to learn more about a European River cruise?
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