Overlooking the Parliament Building in Budapest, Hungary

Have you heard about the new river cruise line, U by Uniworld, the first cruise company ever to target one generational demographic? The new U, which will ply the waters of Europe's Seine, Rhine and Danube beginning in 2018, is pledging that it will offer travelers in the 21- to 45-year-old age bracket (born approximately between 1972 to 1997) a revolutionary new style of cruise.

"We're reinventing the travel industry with U, a fresh approach to cruising…" says a note on the U by Uniworld website.

Onboard, you'll find yoga and classes that include cooking, painting (with wine) and bar mixology. Riverboats will stay in port late into the evening (or even overnight). Onboard Wi-Fi will be complimentary. Sun decks -- the long, flat top deck of a riverboat that's the best place onboard when weather's good -- will feature boutique bars and lounging. Shore excursions offer a nice balance of active choices -- kayaking in the Seine, white-water rafting in Budapest -- with visits to more traditional tourist attractions.

If the concept of a "silent" disco -- an evening event out on deck where passengers dance with earphones on -- is a bit of a head-scratcher for this non-millennial, the most significant thing about U by Uniworld is this: It's not all that different, actually, than what existing river cruise lines, including Uniworld, its sister line, are offering now.

Does this mean we are already cruising like millennials on Europe's rivers? Many lines are increasing time in port. Experiential activities, from bikes onboard for independent touring to guided rides and from hiking to watersports, are part of activity menus. On shore, river companies offer an array of options for connecting with the places they visit; Uniworld itself was a pioneer in beefing up the extra-fee, premium tours some years back, and the concept has spread widely as companies from Avalon to Tauck feature unique experiences in various ports of call. Spa features, from Crystal's ultra-luxe facility on its Mozart to indoor/outdoor pools found on Emerald Waterways and on some Uniworld ships, are big hits. And dining options -- with most lines offering at least two different choices at every meal -- are expanded as much as they can be with the limited space on European riverboats.

So what does U by Uniworld offer its target millennial audience that isn't already available?

What you've got to love, and what may be crucial when it comes to enticing millennials onto a European river cruise, is the lower price; the per day cost, per person with two sharing a cabin, is about $200; about half what you'll pay on more mainstream lines (again, another feature that other generations may also appreciate). Cabins are correspondingly smaller, too; if you want a suite with butler, this won't be the line for you. There's also an edgier vibe onboard, one designed to feel more like a club that happens to be on a river boat rather than a hotel that happens to float. 

Still, there could be a good reason for a company like The Travel Corporation, U's parent, to aim squarely at this particular generation. This summer, The American Society of Travel Agents conducted a "How America Travels National Study" and there were some interesting surprises. One eye-opener was how gung-ho this younger adult generation already is about cruise travel; 61 percent are favorably disposed to try a cruise. When you consider that 56 percent of boomers and 45 percent of X-ers share a similar level of enthusiasm, that's an interesting case for cruise industry investment in serving millennials.

Exploring Moulin Rouge's nightlife in Paris, France

Beyond the statistics, there's a lot to like about the U by Uniworld approach, which is meant for recreationally active and experientially curious travelers. It's like the line is taking all the most interesting new river cruise trends that have developed over the years, and packaging them, with a big shiny red bow, on one product. And even though I miss the line's target demographic, the combination of a more active experience with plenty of choices onboard and onshore -- at a price that's appreciably lower than the current market rate -- is really appealing. Even with the "silent" disco.

But here's the thing I'd miss: When you create a controlled environment based on one particular demographic as your passenger, what could be missed is the exposure to people of different ilks. While there's something to be said for cruising with people who are "just like me," it seems a shame to miss out on the alchemy that comes from meeting fellow travelers from a variety of age groups, finding connections in the most unexpected places, and sharing common interests whatever our age differences or similarities.

--By Carolyn Spencer Brown, Chief Content Strategist

Editor's Note: Cruise Critic is partnering with the American Society of Travel Agents to share stories about trends in cruising. Some other points worth noting about the millennial dynamic and its broader impact on travel, according to the "How America Travels National Study," is that this generation is driven toward authentic experiences and loves small "and big" travel luxuries (who doesn't!). Reviews from fellow travelers are super important when it comes to making purchasing decisions – and here's something that surprised us: Millennials are more likely to seek out travel agents for information, service and bookings, than either of the two older generations. Want to know more about cruise travel? Check out ASTA’s new consumer-focused TravelSense.org.