The Hangover was filmed in Las Vegas in the United States of America.
Chapel
In movie
Real
Fremont Street (between 9th & 10th)
In movie
Real
Jade's Apartment
In movie
Real
Hotel
In movie
Scene where The boys stay at the Caesar Palace for the bachelor party weekend. The lobby, elevator, hallways and entrance were used for filming.
Real
Scene was shot at the famous Caesar's Palace Hotel, where they filmed scenes in the lobby, outside the hotel and on the roof.
Las Vegas
Caesars palace