VENICE, Italy >> Tourists are waiting more than two hours to visit the Acropolis in Athens. Taxi lines at Rome’s main train station are running just as long. And so many visitors are concentrating around St. Mark’s Square in Venice that crowds get backed up crossing bridges — even on weekdays.

After three years of pandemic limitations, tourism is expected to exceed 2019 records in some of Europe’s most popular destinations this summer, from Barcelona and Rome, Athens and Venice to the scenic islands of Santorini in Greece, Capri in Italy and Mallorca in Spain.

While European tourists edged the industry toward recovery last year, the upswing this summer is led largely by Americans, boosted by a strong dollar and in some cases pandemic savings. Many arrive motivated by “revenge tourism” — so eager to explore again that they’re undaunted by higher airfares and hotel costs.

Lauren Gonzalez, 25, landed in Rome this week with four high school and college friends for a 16-day romp through the Italian capital, Florence and the seaside after three years of U.S. vacations. They aren’t concerned about the high prices and the crowds.

“We kind of saved up, and we know this is a trip that is meaningful,” said Gonzalez, who works at a marketing agency. “We are all in our mid-20s. It’s a (moment of) change in our lives. … This is something special. The crowds don’t deter us. We live in Florida. We have all been to Disney World in the heat. We are all good.”

Americans appear equally unperturbed by recent riots in Paris and other French cities. There was a small drop in flight bookings, but it was mainly for domestic travel.

“Some of my friends said, ‘It’s a little crazy there right now,’ but we thought summer is really a good time for us to go, so we’ll just take precautions,” Joanne Titus, a 38-year-old from Maryland, said while strolling the iconic Champs-Elysees shopping boulevard.

The return of mass tourism is a boon to hotels and restaurants, which suffered under COVID-19 restrictions. But there is a downside, too, as pledges to rethink tourism to make it more sustainable have largely gone unheeded.

“The pandemic should have taught us a lesson,” said Alessandra Priante, director of the regional department for Europe at the U.N. World Tourism Organization.

Instead, she said, the mindset “is about recuperating the cash. Everything is about revenue, about the here and now.”

“We have to see what is going to happen in two or three years’ time because the prices at the moment are unsustainable,” she said.

The mayor of Florence is stopping new short-term apartment rentals from proliferating in the historic center, which is protected as a UNESCO heritage site, as mayors of Italy’s other art cities call for a nationwide law to manage the sector.

Elsewhere, the anti-mass tourism movements that were active before the pandemic have not reappeared, but the battle lines are still being drawn: graffiti misdirected tourists in Barcelona away from — instead of toward — the Gaudi-designed Park Guell.

Despite predictable pockets of overtourism, travel to and within Europe overall is still down 10% from 2019, according to the World Tourism Organization. That is partly due to fewer people visiting countries close to the war in Ukraine, including Lithuania, Finland, Moldova and Poland.

In addition, Chinese visitors have not fully returned, with flights from China and other Asia-Pacific countries down 45% from 2019, according to travel data company ForwardKeys.

Tourism-dependent Greece expects 30 million visitors this year, still shy of 2019’s 34 million record. Still, the number of flights are up so far, and tourist hotspots are taking the brunt.

The Culture Ministry will introduce a new ticketing system for the Acropolis this month, providing hourly slots for visitors to even out crowds. But no remedy is being discussed for the parking line of cruise ships on the islands of Mykonos and Santorini on busy mornings.

Spain’s tourism minister, Héctor Gómez, called it “a historic summer for tourism,” with 8.2 million tourists arriving in May alone, breaking records for a second straight month. Still, some hotel groups say reservations slowed in the first weeks of summer, owing to the steep rise in prices for flights and rooms.

Costs are growing as flights from the U.S. to Europe are up 2% from 2019 levels, according to ForwardKeys.

“The rising appetite for long-haul travel from America is the continued result of the ‘revenge travel’ boom caused by the pandemic lockdowns,” said Tim Hentschel, CEO of HotelPlanner, a booking site. “Big cities within these popular European countries are certainly going to be busy during the summer.”

Americans have pushed arrivals in Italian bucket-list destinations like Rome, Florence, Venice and Capri above pre-pandemic levels, according to Italy’s hotel association, Federalberghi.

They bring a lot of pent-up buying power: U.S. tourists in Italy spent 74% more in tax-free indulgences in the first three months of the year, compared with same period of 2019.

“Then there is the rest of Italy that lives from Italian and European tourism, and at the moment, it is still under 2019 levels,” Federalberghi president Bernabo Bocca said.

He expects it will take another year for an across-the-board recovery. An economic slowdown discouraged German arrivals, while Italians “are less prone to spending this year,” he said.

And wallets will be stretched. Lodging costs in Florence rose 53% over last year, while Venice saw a 25% increase and Rome a 21% hike, according to the Italian consumer group Codacons.

Even gelato will cost a premium 21% over last year, due to higher sugar and milk prices.

Perhaps nothing has encouraged the rise in tourism in key spots more than a surge in short-term apartment rentals. With hotel room numbers constant, Bocca of Federalberghi blames the surge for the huge crowds in Rome, inflating taxi lines and crowding crosswalks so that city buses cannot continue their routes.

In Rome and Florence, “walking down the street, out of every building door, emerges a tourist with a suitcase,” he said.

While Florence’s mayor is limiting the number of short-term rentals in the historic center to 8,000, no action has been taken in Venice. The canal-lined city counts 49,432 residents in its historic center and 49,272 tourist beds, nearly half of those being apartments available for short-term rental.

Inconveniences are “daily,” said Giacomo Salerno, a researcher at Venice’s Ca’ Foscari University focusing on tourism.

It difficult to walk down streets clogged with visitors or take public water buses “saturated with tourists with their suitcases,” he said.

Students cannot find affordable housing because owners prefer to cash in with vacation rentals. The dwindling number of residents means a dearth of services, including a lack of family doctors largely due to the high cost of living, driven up by tourist demand.

Venice has delayed plans to charge day-trippers a tax to enter the city, meant to curb arrivals. But activists like Salerno say that will do little to resolve the issue of a declining population and encroaching tourists, instead cementing Venice’s fate as “an amusement park.”

“It would be like saying the only use for the city is touristic,” Salerno said.