On a Wednesday morning in March, Rita Deitchman, 74, was wearing a Royal Caribbean diamond necklace, earrings and bracelets, as she perched on the boardwalk of the cruise company’s 6,988-passenger ship, Wonder of the Seas in San Juan, P.R.

This was Ms. Deitchman’s 196th cruise — her 18th since September 2021, when, after a year and a half on shore while the Centers for Disease Control and Prevention halted sailings from U.S. ports and then the cruise lines worked out their Covid protocols, she got back on a ship. She waved her hands, delighted to greet everyone strolling her way.

“I love to meet people, to socialize,” she said.

Ms. Deitchman is among a small and devoted band of cruise passengers, self-described “cult cruisers” who book back-to-back cruises for, well, more or less forever, aiming to essentially live on board. Since she resumed cruising, she has spent only one day on shore for laundry and regrouping while she waited for her next sailing.

When the pandemic shut down all sailing from United States ports, these cruise enthusiasts basically lost their homes.

So for them, the return to cruising was more than an invitation to book another vacation. It was a welcome home.

While tales of these cult cruisers are primarily anecdotal, when Cruise Critic, a leading cruise review site, did a survey in 2017 of 3,100 people about the concept of retiring at sea, 59 percent said they had a strong interest in the idea, and another 27 percent said they’d consider it if the price were right.

“The average person is getting their week vacation and maximizes the week,” said Mark Tamis, the senior vice president of hotel operations for Royal Caribbean International. “But it’s not that uncommon to try to live on the ship.”

Ms. Deitchman and her husband moved from Scranton, Pa., to a small condo in Fort Lauderdale, Fla., three years ago so they’d be closer to the ships. But they never expected to actually reside in their tiny condo for as long as they did.

“It was just meant to be a place to do laundry while we waited for the next cruise,” she said.

Last September, when restrictions on cruises eased and she was given the green light to leave her condo and return to the ships, Ms. Deitchman said she was so happy, she cried. And then, she said, she ran to the lounge outside her suite on the Freedom of the Seas, and waited for the friends she knew would eventually join her there for her first sailing.

“We feel like they’re our family,” she said. Ms. Deitchman has two adult children, who she jokingly explained don’t treat her as nicely as she’s treated on cruises.

Stuck on dry land

As they waited to resume cruising, many of the devoted fans continued to allocate their time to cruising, though they were land-based.

Denorah Irby, 53, of Bridgeport, Conn., spent her time during the pandemic looking at cruise videos on YouTube with her husband, Curtis. Those videos weren’t necessarily of cruises they’d taken or planned to take. They were simply videos of strangers on cruises, as the Irbys desperately tried to get their cruise fix off the water.

“It was a tough two years,” Ms. Irby said.

Others devoted their time to posting on the cruise lines’ very active Facebook fan pages (or rather, grumbling about the unfairness of the cruise suspension — and speculating on when they could start cruising again).

Now that cruises are back, more than 6 million passengers have sailed in nearly 90 markets worldwide, including more than 2 million from U.S. ports since June, according to the Cruise Lines International Association, an industry group. Already, bookings for cruise departures for the second half of 2022 have outpaced bookings in 2019 by 37 percent, according to Cruise Planners, a travel agency focused on cruising. A quarter of all cruise bookings at the moment are for 2023.

On a quiet evening in March, aboard the Wonder of the Seas, Donna Muller, 66, sat in the main dining room as the ship sailed from San Juan to Nassau, the Bahamas, reminiscing about her two landlocked years.

“We really were homesick for our second home,” Ms. Muller said, pausing to order her dinner without glancing at the menu. “It’s Tuesday, right? I know Tuesday’s menu.” (She’s been on 115 cruises.)

Frank Shumard, 69, had a big plan for when he retired from his position as a transportation safety director for Waste Corporate of America six years ago: He would move from his home in Shell Knob, Mo., to a condo in nearby Table Rock Lake, and he’d spend his winters cruising and his summers on the lake. “I didn’t even care where I was going when I was on the cruise — I was happy just to sit up on the lounge chair and watch the ocean go by.”

When the pandemic crushed his plans, it was the closest Mr. Shumard came to being clinically depressed, he said. During the pandemic, Mr. Shumard felt totally lost.

He cheered himself up by creating a “drink of the day,” and posting it to the Holland America Cruise Facebook fan page. Eight hundred drinks later, Mr. Shumard and his partner, Lynn Shriver, climbed back onboard, and immediately spotted his favorite bartender.

“It was so nice to see a face that I knew, and to shake hands, and it was such a relief to see that he was there, that he was well: It was magical,” Mr. Shumard said.

Loyal to their lines

All the major ship lines, from Royal Caribbean to Princess to Holland America, have their own loyalty programs that reward frequent sailors with everything from drink coupons to room upgrades. But while the perks are big business — and the cruisers proudly wear their loyalty badges in the forms of pins and other jewelry — many cult cruisers say they don’t return to the same lines because of the rewards.

Instead, they pledge fealty to a specific cruise line for how it syncs with their personalities and desires. The Royal Caribbean cruisers, for example, say they love the friendly crew and passengers they consistently meet on the ships. (The cruise line says one of its biggest fans has spent 9,500 nights onboard.) Viking cruisers point to the line’s luxury and all-inclusive pricing (Wi-Fi, basic alcohol packages during meals and shore excursions are included in the base fare). Holland America fans return for the crew, the food and the intriguing itineraries, like a 35-night cruise that makes stops along England, Scotland, the coast of Norway, Iceland and the Norwegian-controlled Arctic island of Spitsbergen. Many. Many Holland America ships include outposts of B.B. King’s Blues Club, and the focus on live music also draws many repeat visitors.

Linda Sloan Chalmers, 67, a retired piping routing designer for petrochemical refineries in Ocean Shores, Wash., tries her best to live on the ships, choosing the longest itineraries she can find. When cruising resumed, after taking a quick cruise to Alaska on Holland America, her favorite cruise line, to make sure she approved of it’s Covid procedures (she did), she went ahead and booked three more cruises, for a total of 143 nights onboard.

When Ms. Chalmers was locked down at home, she spent her time knitting, cooking and reading, which is what her alter-ego enjoys, she said. On the ships she said, her true personality shines — and that’s what she loves about cruising.

As soon as she boards, Ms. Chalmers heads to the Blues club (she makes it a priority to book all her sailings aboard ships that have her favorite venue) to see her beloved bartenders and crew members, greeting them enthusiastically.

Even being on the ill-fated Coral Princess, which pulled into Miami at the start of the pandemic with the bodies of two passengers who had died from Covid and a dozen other people who had tested positive, didn’t dampen Alice Gottlieb’s cruise obsession.

Ms. Gottlieb, 74, a retired New York City principal, said she’s traveled the world by ship, having taken 70 cruises, and the pandemic won’t stop her. She emailed from a six-night Caribbean Princess cruise in March — her first since the pandemic.

“The best part of the cruise is walking up the gangway: It’s so wonderful to be back on board,” she wrote.

Diane St. John’s retirement plan involved seeing the entire world through the lens of a Holland America cruise. The 77-year-old retired English teacher, who lives in San Luis Obispo, Calif., when she’s not cruising, said she was halfway done with her eighth around-the-world cruise (each of which is about 120 days) when the pandemic hit, and she was forced to disembark in Fremantle, Australia, barely making it out of the country before the borders closed. “We made it out by the skin of our teeth,” she said.

Ms. St. John’s first post-pandemic cruise was a back-to-back cruise on the Koningsdam: A California coastal cruise followed by a week to Mexico. Then, she took three back-to-backs.

“I just felt that we were at home, and we were so comfortable,” Ms. St. John said. “It was like being home again, and wrapped in a fuzzy blanket.”

She didn’t cry, though.

“I save my tears for disembarking after four months of a world cruise,” she said.

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