VENICE, Italy — Under the gaze of the world’s media, the fragile lagoon city of Venice launched a pilot program Thursday to charge day-trippers a 5-euro entry fee that authorities hope will discourage visitors from arriving on peak days and make the city more livable for its dwindling residents.

Visitors arriving at Venice’s main train station were greeted with large signs listing the 29 dates through July of the plan’s test phase, as well as new entrances separating tourists from residents, students and workers.

Stewards were on hand to politely guide anyone unaware of the new requirements through the process of downloading the QR code to pay the fee.

“We need to find a new balance between the tourists and residents,’‘ said the city’s top tourism official, Simone Venturini. “We need to safeguard the spaces of the residents, of course, and we need to discourage the arrival of day-trippers on some particular days.”

Arianna Cecilia, who lives in Rome and was visiting Venice for the first time with her boyfriend, said it felt “strange” to have to buy a ticket to enter a city in her native Italy, and then pass through a tourist entrance.

The couple were staying in nearby Treviso, and had paid the fee and downloaded the QR code as required prior to arrival.

Workers in yellow vests carried out random checks at the train station, and anyone caught faces fines of 50 euros to 300 euros — though officials said “common sense” was being applied for the launch.

The requirement applies only for people arriving between 8:30 a.m. and 4 p.m. Outside of those hours, access is free and unchecked.

Venice has long suffered under the pressure of over-tourism, and officials hope the pilot project can help provide more exact figures to better manage the phenomenon.

The city can track the number of hotel visitors — which last year numbered 4.6 million, down 16% from pre-pandemic highs. But the number of day visitors, which make up the majority of the crowds in Venice, could only be estimated until recently.

A Smart Control Room set up during the pandemic has been tracking arrivals from cell phone data, roughly confirming pre-pandemic estimates of 25 million to 30 million arrivals a year, said Michele Zuin, the city’s top economic official. That includes both day-trippers and overnight guests.

But Zuin said the data is incomplete. “It’s clear we will get more reliable data from the contribution” being paid by day-trippers, he said.

Venturini said the city is strained when the number of day-trippers reaches 30,000 to 40,000. Its narrow alleyways are clogged with people and water taxis packed, making it difficult for residents to go about their business.

Not all residents, however, are persuaded of the efficacy of the new system in dissuading mass tourism. Some say more attention needs to be paid to boosting the resident population and services they need.

Venice last year passed a telling milestone when the number of tourist beds exceeded for the first time the number of official residents, which is now below 50,000 in the historic center with its picturesque canals.

“Putting a ticket to enter a city will not decrease not even by one single unit the number of visitors that are coming,’‘ said Tommaso Cacciari, an activist who organized a protest Thursday against the measure.

“You pay a ticket to take the metro, to go to a museum, an amusement park; you don’t pay a ticket to enter a city. This is the last symbolic step of a project of an idea of this municipal administration to kick residents out of Venice,” he said.

Venturini said about 6,000 people had already paid to download the QR code, and officials expect paid day-tripper arrivals Thursday to reach some 10,000.

More than 70,000 others have downloaded a QR code denoting an exemption, including to work in Venice or as a resident of the Veneto region. People staying in hotels in Venice, including in mainland districts like Marghera or Mestre, should get a QR code attesting to their stay, which includes a hotel tax.

The tourist official says interest in Venice’s pilot program has been keen from other places suffering from mass tourism, including other Italian art cities and cities abroad such as Barcelona and Amsterdam.

Marina Rodino, who has lived in Venice for 30 years, is opposed to the new plan. She was passing out mock EU passports for “Venice, Open City,” underlining the irony of the new system, and challenging its legal standing with citations from the Italian constitution guaranteeing its citizens the right to “move or reside freely in any part of the national territory.”

Rodino has seen her local butcher close and families leave her neighborhood near the famed Rialto Bridge as short-term apartment rentals spring up. But she said the new entrance fee requirement will still allow young people to flood the city in the evening for often rowdy gatherings.

“This is not a natural oasis. This is not a museum. It is not Pompeii,” she said. “It is a city, where we need to fight so the houses are inhabited by families, and stores reopen. That is what would counter this wild tourism.”