Local press reports and water taxi drivers say George Clooney and his British fiancé lawyer Amal Alamuddin, are in Venice for their wedding.
Reports have speculated that the couple will have two ceremonies, one on Saturday, followed by a civil ceremony on Monday.
Bono, Cate Blanchett and Matt Damon are reportedly among the guests in the Italian lagoon city for the three-day celebration.
Security is tight in Venice where city officials plan to close a walkway to keep crowds away from the wedding. But that may not be enough to stop the most determined Clooney fans from trying.
“We are waiting for all the guests for the Clooney wedding,” said teenage Clooney fan Lara. “We are hoping that Quentin Tarantino and Robert de Niro come because they are friends.”
“This is one of the most beautiful places in the world, how could you not get here, it’s romantic, it’s the epitome of love here,” said American tourist, Tammy Schabel.
Clooney has been a frequent visitor to Venice, notably to movie premieres at the annual film festival.
It is his second marriage and Alamuddin’s first.