Dozens of law enforcement and civil defense officials patrolled Bracciano's medieval streets, and vehicles were banned from the historic center surrounding 15th-century Odescalchi Castle — the likely venue for the celebrity wedding.
Gaggles of teenagers began gathering under the castle's walls early in the morning.
To see wedding morning photos, click here.
"I want to see at least one of them — even if it's not Tom Cruise," said 15-year-old Erica Bandiera.
"I want to see Beckham's wife," said her friend Luca Costanzi, 15, with a huge grin.
Guests were expected to include "Mission Impossible III" director J.J. Abrams, Brooke Shields, Jennifer Lopez and Lopez's husband, singer Marc Anthony, Will Smith, and soccer star David Beckham with his pop-star wife Victoria.
The historic town's narrow streets teemed with journalists and camera crews, as the Odescalchi family flag fluttered over the castle's towers.
"This is an honor for us," said Marianna Riso, 31, who came to Bracciano from the nearby town of Anguillara in hopes of getting a glimpse of one of the celebrities. "(Cruise and Holmes) really are known all over the world and they chose Bracciano. It's an honor."
Locals found their own ways to welcome the bride- and groom-to-be.
At the Il Ristorantino dining spot, Palazzini offered a "Top Gun" menu that included fettuccine with seafood called "Mission Impossible" and apple pie with cream and hot chocolate named after Suri, the couple's daughter. At the nearby Trattoria del Castello, guests could order a "Tom e Kat" — a basket of parmesan cheese with truffles and mushrooms.
"Wishing you love and happiness," read one sign written in English and taped to the window of a coffee shop.
"Congratulations Tom and Katie," said a sticker on the window of a clothing store, whose two other windows displayed a wedding dress with a photograph of the couple, and a "Top Gun" theme with aviation outfits and jackets, and a poster of Cruise as Maverick, the pilot he played in the movie.
On Friday evening, Cruise and Holmes attended a reception at a villa on a hill overlooking the Italian capital, and were still inside Rome's luxury Hassler hotel on Saturday morning.
Bracciano Mayor Patrizia Riccioni said the celebrity couple would wed in a Scientology ceremony — at the castle, 27 miles north of Rome.
Scientology ceremonies contain many elements of traditional weddings, including rings and vows. But they also include certain Scientology fundamentals, including vowing never to go to bed without communicating about any differences.
Scientology rites are not legally recognized in Italy, and would have to be preceded or followed by a civil union.
Riccioni's office had not received a request to celebrate a civil wedding as of early Saturday.