The Pompeii archaeological park plans to limit visitor numbers to 20,000 a day and introduce personalized tickets starting next week in a bid to cope with over-tourism and protect the world heritage site, officials said Friday. The move comes after what authorities called a record summer that saw over 4 million people visiting the world-famous remains of the ancient Roman city, buried under ash and rock following the eruption of Mount Vesuvius in 79 A.D.

The park’s director Gabriel Zuchtriegel said visitors to the main archaeological site now exceed an average of 15,000 to 20,000 every day, and the new daily cap will prevent the numbers from surging further. “We are working on a series of projects to lift the human pressure on the site, which could pose risks both for visitors and the heritage (that is) so unique and fragile,” Zuchtriegel said.