Cruising in Europe offers some advantages over taking a tour or traveling independently. Perhaps the most compelling benefit is that on a cruise you board the ship, unpack once, and then your hotel room travels with you from place to place.

This is so much easier than changing hotels every two or three nights that it’s no wonder that the number of cruise ships in Europe just keeps growing.

There are two kinds of cruises in Europe – ocean cruises and river cruises. And both offer the convenience of unpacking just once. But European river cruises can cost twice as much as ocean-going cruises.

Here’s why.

Most of the cruise ships in the Mediterranean can carry between 700 and 2,500 passengers. Most European river cruise ships carry around 100 at the most. The buying power of the mega-ships means that they pay much less for everything from steaks to sheets.

Basically, it costs a big ship much less to feed, house, and entertain a passenger, and that savings is passed onto passengers in the form of lower cruise fares.

But mega-ships can make up for the lower price by selling passengers additional services, both on and off the ship. Since many of Europe’s most appealing cities – including London, Paris, and Florence – are inland, passengers who want to see these places need to purchase shore excursions.

And spa services, fine dining, and lessons and classes are also available for purchase onboard. All these sources of revenue help the bigger ships sell their cabins at a more competitive price.

Size limitations prohibit cruise ships from offering the same amenities and services as the ocean vessels. And many cruises include shore excursions, wine with lunch and dinner, tips, and other “extras” in the price. Without a lot of incidentals to charge for, river cruises have to cover their expenses with the base cruise fare.

Once you understand how cruises make their money, you can make an informed decision about whether or not a river cruise would cost you more or less than an ocean cruise.

Because river cruises travel right through the heart of Europe, you don’t need to spend any time or money to see the sights you came to see. In most cases, they’re right at your doorstep. And an orientation tour of the city is usually included.

Most of the river boats have bicycles onboard that passengers can take ashore if they want to explore areas they can’t see on foot. And the scenery from the boats is terrific day and night.

If you want to experience Europe on a more personal level, you don’t care about spa treatments, fitness centers, or nightly entertainment, and you enjoy a relaxed, casual ambience, a river cruise might end up being less expensive for you in the long run – even if the cruise fare is twice as much.