Napoleon once referred to the Danube River as the "Queen of Europe's Rivers," a fitting title for Europe's second-longest river. It measures 1,775 miles long and up to almost one-mile wide and touches 10 countries -- Austria, Bulgaria, Croatia, Germany, Hungary, Moldova, Romania, Serbia, Slovakia and Ukraine -- and four capitals. That alone has made the Danube a vital transportation route for more than 2,000 years.
Today, ships can navigate 87 percent of the waterway's length, meaning Danube River cruises can sail from the North Sea to the Black Sea. The Main-Danube Canal, which got its major start in the 18th century, was completed in 2002 when the final piece was put in place for the 106 mile, 16-lock waterway.
As you sail, you'll pass ruins of ancient castles, lush vineyards that produce some of the area's finest wines, sleepy river towns and bank-side recreational paths where you can wave hello to cyclists and horseback riders. When you dock, you'll embark on fascinating journeys through cities that sport both medieval and modern influences.
Here are our best tips for a Danube River cruise.
Many of the towns, villages and cities on a Danube River cruise have cobblestone streets and uneven surfaces, which can make walking more challenging. You might also have to climb steps or walk up small inclines to visit castles, churches and vineyards so packing sensible footwear is essential.
Some cruise lines carry bikes onboard that you can use in port cities, but even if that's not the case, many of the cities offer bike tours and bike hire schemes. Both Vienna and Budapest offer electric bike tours, too, which are a lot of fun for a little less work.
If you're prone to motion sickness, have medication handy. Although river cruising is generally calmer than ocean cruising, the slight shaking of the ship while going through the locks might bother an extra-sensitive stomach.
You'll appreciate binoculars to help you zero in on the landscape, especially when you're doing scenic cruising through the Wachau Valley, Austria's wine country, between Melk and Vienna. If you forget, the ship might have extras.
They usually cost a little more, and although a balcony is generally a nice addition, opening the door often invites bugs. Plus, rooms on river ships tend to be smaller than those on ocean-bound ships, and you'll probably be out of your room most of the time anyway. Advantageous viewing areas are only a short walk away.