The line will attract mature, well-traveled guests looking for high levels of personal service and luxury, such as butlers to every suite, upscale dining, wine sommeliers and 24-hour room service.

The ships will be English-speaking and it is likely many Riverside guests will already have sailed with Crystal and welcome the opportunity to travel on familiar vessels that will be little changed under the Riverside brand.

Reflecting the founding company's ethos, the ships have a stylish but friendly and relaxed atmosphere. Guests from mainland Europe typically dress up a little more in the evening than guests from the U.S, and smart-casual attire is the norm. There are no formal nights. For daytime clothes are casual and comfortable and suited to changeable European weather.

Yes and no. Riverside breaks the river cruise norm with a very flexible "a la carte" pricing policy where guests can choose the fare and inclusions that are right for them. Prices lead in with a cruise-only fare which covers full-board meals, wi-fi, gratuities onboard, and ashore and airport transfers. From this basic fare guests can opt to add drinks and/or excursions. Riverside says this pricing policy allows guests to make a choice, such as exploring ports of call independently or with their own private guide rather than going on group shore tours. It also means that those who prefer not to drink or go on shore tours are not subsidising those that do. Cruises can also be booked with or without air travel.

In addition to classic walking tours that introduce guests to destinations being visited, Riverside offers one-of-a-kind experiences. These include a balloon ride over Budapest and helicopter flights over the Austrian alps and UNESCO-listed Wachau Valley. There are also active options such as e-bike rides and hands-on and immersive cultural tours including craft workshops and breakfast on a family farm in Serbia. The onboard concierge is also available to assist guests with bespoke experiences.

Best for: 40+ young-at-heart travel enthusiasts looking for fine dining and luxuries including butler service and rich experiences.

Not for: Budget cruisers and young families