Odescalchi had long been the anticipated wedding site, and Italian media have reported that the ceremony will be held in the castle's Hall of the Caesars.
The $50,000 fee to use the facility has been waived, because Bracciano mayor Patrizia Riccioni wants to thank the couple for all the attention they've brought her town, Bush reported.
More on Their Wedding
"I want to thank Tom Cruise and Katie Holmes for choosing this venue for such an important event," Riccioni said.
She added that she'd given them a small silver sculpture of the castle as a gift, with a card reading, "A sincere note in sign of gratitude from the city of Bracciano, for having chosen it as the place where to crown your dream of love."
Riccioni also said she'd like to grant the Cruises honorary citizenship "because they have brought so much to our little village."
For regular updates on the Cruise-Holmes wedding, check out our Tom & Katie Wedding Blog.