(CNN) — From steam-powered ships, to mega-liners, the cruise industry has been through quite a transformation over the years. And the market has skyrocketed.
Back in 1970, an estimated 500,000 people went on a cruise holiday. That figure had jumped to five million by 1997.
So what brought about this sudden surge in interest? According to industry experts, it was mainly down to a certain TV show with a catchy theme tune.
"Come aboard, we're expecting you!"
Produced by TV legend Aaron Spelling,"The Love Boat" first aired in 1977 and went on to become one of the most successful shows in TV history during its decade long run.
The program, which is still available on streaming services such as Paramount Plus, partnered with Princess Cruises, and episodes were filmed aboard various Princess Cruise ships, the Pacific Princess and Island Princess being the most noted. 'Greatest product placement'
"The Love Boat" centred around the adventures of the crew and passenger on board a luxury cruise ship.
Everett Collection
It's spawned various spin-offs. The latest, reality dating competition show "The Real Love Boat," will be filmed on board a Princess Cruise ship, just like the original show, and is due to air on CBS later this year.
Based on a non-fiction book written by former cruise director Jeraldine Saunders, "The Love Boat" centered around ship captain Merrill Stubing (played by Gavin MacLeod) and his on board crew, while different guest actors played passengers each episode.
The show has since been described as "the greatest product placement" ever, serving as a complete introduction to cruising for many of its avid viewers.
"'The Love Boat' really created the cruise industry," says Michael L. Grace, who worked as a scriptwriter on the program during the 1980s. "Because you had 50 million people watching, and they all wanted to go on a cruise."
Several modern cruise lines existed when the show began, including Princess, founded in 1965 with a single ship cruising to Mexico. Royal Caribbean had launched in 1968, and Carnival Cruise Line was founded in 1972.
But the cruising demographic was very different to what it is now.
"The Love Boat" stars Fred Grandy who played "Gopher," Lauren Tewes (Julie McCoy), Gavin MacLeod (Merrill Stubing), Bernie Kopell ( Dr. Adam Bricker) and Jill Whelan (Vicki Stubing) pictured on set.
Everett Collection
Although cruise companies were apparently keen to attract younger passengers, many people simply didn't know much about cruising, and those who did had a very specific idea of it.
"Back in the day, people would say cruising was for the nearly dead or newlywed," says cruise journalist Carolyn Spencer Brown, chief content officer for Cruise Media, LLC.
"So when 'The Love Boat' came on and showed people of all ages and races having fun and being lively on a cruise ship, that opened up cruising to a world that didn't really know it existed."
Each week, tens of millions of people around the world would tune in to follow the exploits of Captain Stubing, Dr. Adam Bricker (Bernie Kopell), cruise director Julie McCoy (Lauren Tewes), bartender Isaac Washington (Ted Lange) and the captain's daughter Vicki, played by Jill Whelan, and suddenly going on a cruise soared to the top of many a wish list.
"They [the passengers] would come on the ship," Grace says of the formula for the hour-long show.
"They'd have a problem. Then the problem is solved and they all come together again. They [the episodes] were like small movies."
Cruise-building boom
Princess ships Pacific Princess, pictured, and Island Princess were "the original floating stars" of "The Love Boat."
Everett Collection
The launch of the "The Love Boat" came at a time when the vast majority of cruise ships on the water were former liners that had been converted. There were few new ships in service.
However, this quickly changed when demand shot up thanks to the success of the show.
"It [the show] did so well that Princess Cruises were selling out their ships," cruise historian Peter Knego tells CNN Travel. "And that led to the first boom of new cruise ship building in the early 1980s."
The fact that scenes from "The Love Boat" were occasionally filmed aboard real life cruises, with the passengers serving as extras, only added to the appeal.
"So many cruise lines want to create experiences for you that you probably couldn't create on your own," notes Spencer Brown.
The success of the show prompted a boom in cruise ship building. Royal Caribbean's MS Sovereign of the Seas, considered the first mega ship, launched in 1998.
Hauke-Christian Dittrich/dpa/AP
"That [becoming an extra on a popular TV show] certainly qualifies as something that doesn't happen to most people."
Keen to strike while the iron was hot, existing cruise lines began building brand new purpose-built cruise ships in order to cater to this fast-growing market, while new companies emerged like Celebrity Cruises, founded in 1988.
"Back then, to build new cruise ships, that was a big deal," says Knego.
During the 1980s, almost 40 new cruise ships were constructed, including Tropicale, from Carnival Cruise Lines and Royal Princess, Princess Cruises' first purpose-built cruise ship.
"It [Royal Princess] had new features like balconies, which were pretty rare with mainstream cruising," he adds.
As more cruise lines emerged and began competing with each other, cruising became more affordable, expanding the market even further.
Entertainment focus
"The Love Boat" become one of the most successful TV shows of all time.
Princess Cruises
"The Love Boat" may also have played a part in the heavy entertainment focus we see on modern day cruise ships.
Outlandish musical performances were often featured on the "The Love Boat," and they proved to be a big hit with viewers.
During one of the show's specials known as "The Love Boat Follies," iconic stage and screen stars Della Reese, Ethel Merman, Carol Channing and Ann Miller sing a rendition of "I'm The Greatest Star" from the 1968 musical "Funny Girl" together.
"It was very spectacular," says Grace, who is working on a book about the impact of "The Love Boat."
"And what was so strange is, when they would flash back to the people watching in the audience, it was like a small little club. But the stage was the size of a West End theater."
Off screen, the Island Princess and its sister ship Pacific Princess, the two ships primarily used for filming towards the start of the series, held main stage production shows that became hugely popular with cruising fans.
This led to the introduction of some grand new features on cruise ships in later years.
"Princess and other cruise lines went on to build ships with state of the art showrooms with huge stages, sound and lighting effects that are now standard on modern cruise ships," says Knego, adding that the modern atriums seen on cruise ships today can also be traced back to "The Love Boat" ships.
"The two deck lobbies with the grand staircase that was replicated for the studio shoots were early versions of the big atriums that are now popular features on modern cruise," he says.
Romantic adventures
Hollywood icon Carol Channing was among the many big stars who appeared in the series.
Everett Collection
Romance was understandably a very important factor in "The Love Boat." While the relationship plots certainly kept viewers entertained, Spencer Brown stresses that this focus was also beneficial when it came to maintaining the notion that "cruises really are quite romantic."
"For a long time, Princess had all sorts of enhanced amenities that were pointed to romance," she adds.
"They really embraced this concept all the way through. You could have a balcony, sunset dinners, and rose petals strewn on your bed. All of these lovely, romantic things."
Long-time cruise enthusiast Judi Patterson, who met her husband Andy when he was working on board another cruise ship, P&O's SS Oriana, was a fan of "The Love Boat," but says her own cruising experiences were very different to what was portrayed on screen.
"It [the show] bears no resemblance to reality," says Patterson. "But it was fun. I don't know if people actually believe that that's what happens [on cruise ships].
"It was fun to watch and think that these things might possibly happen."
"The Love Boat" reruns were still airing around the world years after its last episode, and the show's fan base has remained incredibly loyal.
Lasting legacy
Hollywood stars Greer Garson, second from left, and Howard Duff, with series regulars Ted Lange, far left, and Lauren Tewes.
Everett Collection
Spencer Brown, who also met her now husband on board a cruise ship -- the couple even got engaged on a cruise -- believes that the partnership between "The Love Boat" and Princess Cruises has been the key to its longevity.
"They truly embraced each other in a way that was really genuinely heartfelt," she says."The cast members became such a part of the cruise line, and they still are."
Princess Cruises often holds reunion cruises, with the actors from "The Love Boat" appearing as special guests. The next one is scheduled for October 2022, sailing from Los Angeles to Mexico. "People stand in line for hours just to get their picture taken with cast members," says Knego, who's due to attend the upcoming reunion. "They [the cast] sign autographs and it's quite a wonderful situation to this day."
MacLeod was a regular on the popular cruises until his death in 2021.
"People always ask us why 'The Love Boat' was so popular and I always say it's because it gave people something to dream about," the actor said back in 2015. Royal Caribbean's Wonder of the Seas is currently the world's biggest ship.
Sigrun Sauerzapfe/Royal Caribbean
"They could dream about being out on the open seas on a cruise and discovering the worlds' greatest destinations, dreaming about love and of course happy endings since the shows always ended on a high note. I'm proud to have played a role in the growth of the cruise industry."
Now a billion dollar industry, cruising has evolved considerably since "The Love Boat." There are currently over 1,200 cruise ports across the world.
Royal Caribbean's MS Sovereign of the Seas, considered to be the first mega ship, with a passenger capacity of 2,850, took its maiden voyage in 1998, while Disney Cruise Line was established that same year.
At present, Royal Caribbean's Wonder of the Seas, an 18-deck cruise ship that has capacity for 6,988 guests and 2,300 crew members, is the current record holder for world's biggest ship. While the Covid-19 pandemic undoubtedly devastated the cruise industry, and the past two years have been shaky, things are looking up once again.
Last month, leading global cruise industry trade group Cruise Lines International Association, announced that 75% of its member ships had already returned to service, and nearly all were forecast to be back by late summer. In 2015, Princess Cruises introduced "The Isaac" cocktail, a drink inspired by Ted Lange's character on the series.
Bret Hartman/AP/Princess Cruises
"To me, the cruise industry is almost a victim of its success," says Knego, who runs YouTube channel MidShipCinema, which is dedicated to old and new cruise ships."Because the mainstream cruise ships now carry up to 5,000 people and they're absolutely massive. "They don't have the same kind of intimacy that you had back when ships only carried 800 or maybe 1,200 people like the Love Boats."
However, there are various cruise companies that offer smaller ships for those keen for a more Love Boat style cruising experience.
Patterson and her husband have taken many trips with leading small ship cruise line Viking, and will be setting off on a world cruise in January 2023.
"We only travel on small ships now," she says, noting that it's slightly more expensive to travel on smaller ships. "We had our turn on the bigger ones."
New chapter
"The Real Love Boat ," a reality dating competition series inspired by show, will be filmed on the Regal Princess.
CBS ENTERTAINMENT/Princess Cruise/CBS
Knego managed to photograph the Island Princess during its final days at a scrapyard in India and was able to rescue a few of the furnishings and ornaments, including a bronze mermaid sculpture and some of the furniture from the lobby area of the ship.
He hopes to bring some of the items onto the "The Love Boat" reunion cruise this fall so that the fans on board "can have a tactile connection with the original ships."
Later this year, "The Real Love Boat" will see another Princess ship, the Regal Princess, take center stage in a TV show, albeit on a very different format.
"It's good for the cruise industry," Spencer Brown says of the upcoming series, albeit noting that a reality show is "a pretty radical reinterpretation" from the original show.
"It's good for all of cruise, because it tells a different story. It tells a fun and romantic story."
Top image: "Love Boat" cast members, from left, Ted Lange, Gavin MacLeod, Jill Whelan, Bernie Kopell, Lauren Tewes and Fred Grandy. Credit: TV Guide/courtesy Everett Collection