In Europe, Viking use their signature vessels, longships, which are basically identical in design, offer luxurious accommodation and dining facilities, and can carry 190 passengers. These ships are spread over 4 decks, and all cabins are at least outside cabins, with a full view of the river and surroundings. On some sailings in Europe you may also come across the "baby" longships which although of a similar aesthetic to the main longships, only have three decks, so cabin options will vary.
In Russia, the ships will be more varied as they are refurbished older vessels, and not custom built by Viking. These ships are able to carry more passengers (up to 204 depending on the ship) and have a single dining area. They do offer though a wider variety of cabin and suite, but some public areas may seem a bit smaller. Generally though the design remains Scandinavian, but with a Russian flair.
The ships that operate in Asia are once again more varied. The Viking Emerald which sails on the Yangtze river is the largest in the Viking fleet, closer to a small ocean cruise ship than river, and able to carry up to 256 passengers, and also has more public spaces, whereas the Viking Mekong is one of the smaller vessels only carrying up to 60 guests, and is unlike any other Viking ship, designed as it is to mimic a traditional French colonial riverboat.
River cruises are all about the destinations, more than the stay on-board experience, but don't worry, the stay will leave you relaxed and pampered, feeling fresh for each excursion you decide to take to visit the marvellous locations on your journey. Onboard, there are few activities in which to engage but the occasional onboard lecture, or local dance or music troupe tends to draw a crowd. Evening music (most often a piano player) is often popular too.
If you are looking for an expert in river cruises, then Viking River Cruises is the company to choose. Luxury cruises, beautiful destinations, and amazing experiences, available to every guest who chooses to sail with the most popular river cruise company in the world.