Livorno coast guard patrollers monitored the stretch of beach for days before making their move, officials said.
Owners were invited to claim their beach paraphernalia at the coast guard station, but only if they were prepared to pay the €200 fine. Seizures were also carried out in Salerno, Abruzzo and along the Adriatic Riviera.
"We are being pretty severe about this because we believe the public areas need to remain accessible to all, not just those who want to be first in line or try to make money from something that is open to everybody," said Coast Guard Commander Cosimo Nicastro.
As the sun began to set on an umbrella-lined stretch of public beach on the Adriatic Riviera, holidaymaker Atlin Uka said he wouldn't dream of leaving his gear behind.
"We always take our stuff home with us because you never know who might walk away with it," said Uka, who had lugged two umbrellas, a deck chair, four towels, two large beach bags and a scattering of beach toys to a prime spot a few feet from the Adriatic Sea near Ravenna where he was on holiday with his wife, sister-in-law and two children.
"It is a lot to haul, but you don't want to show up the next day and find it all gone. We just try to get here early."
Illegally planting your deck chair or umbrella to save a spot is not the only sanctionable offence at the beach.
More than 3000 coast guard personnel and 300 naval units are patrolling the 8000km of Italian coast this summer as part of a larger operation to make sure the tourism season runs smoothly.
Coast guard officials said they are also cracking down on those who take their yachts or sailboats too close to swimming areas, and carefully regulating fishing, diving and snorkeling in protected marine reserves.
In 2015 the coast guard made 239 seizures and filed 690 criminal complaints against beach goers who broke the law. This year's ban on leaving unattended beach gear is in force through September 18.
"There is a big presence of people on our beaches this year," Commander Nicastro said. "First and foremost we look out for people's safety, but we also to ensure legality and security so nothing impedes of the relax and fun of the holidays."