The mayor of Venice has likened the “bravery” of his decision to charge day-trippers an entrance fee to the city to that of the legendary Venetian explorer Marco Polo. Venice will become the first mayor city in the world to adopt such a measure when the long-mooted €5 (£4.30) fee comes into force later this month. Luigi Brugnaro said the objective was not to make money for Venice’s coffers but to “defend” the lagoon city, which attracts an estimated 40,000 visitors a day, and make it more liveable. The tickets are bookable online and apply on 29 peak dates between 25 April and 14 July. Venice authorities consider 2024 as being the experimental phase of the initiative. “We have a duty to preserve the great historical centres of the world,” Brugnaro told reporters in Rome. “Over history, nobody has risked ever trying this … no politician would do what I am about to do. If it works, everyone will say it’s banal, and if it doesn’t work, it will create criticism and a bad impression.” Brugnaro, an entrepreneur, said that when he thought of brave, risk-taking people, Polo, who set off from Venice in 1271 at the aged of 17 and spent more than two decades travelling through Asia, sprang to mind. “He didn’t know where he was going, there was no GPS … and he arrived in China. Then he returned to Venice with important know-how.” Day-trippers will be provided with a QR code once they’ve booked their ticket, which is required only for access to Venice’s historic centre. Stewards will carry out checks at various access points and visitors risk fines of up to €300 if they arrive without a code. Residents, commuters, students and children under the age of 14 are exempt, as are tourists who stay overnight. Critics have accused the measure of being “unconstitutional” and restrictive on freedom of movement, while others have argued that it could deter visitors. Venice authorities have been under pressure to come up with ways to manage tourism in the fragile city while also addressing depopulation on Venice’s main island, which since the early 1950s has lost more than 120,000 residents. Last year, the number of beds available to tourists on the main island surpassed the number of year-round residents – now fewer than 49,000 – for the first time. Brugnaro said he hoped the entrance fee scheme would develop into something that other cities grappling with overtourism could replicate.