Without realizing, most people are already aware of the Hollywood Hills neighborhood, the area surrounding the famous Hollywood sign. The area is affluent and exclusive and includes the neighborhoods of Hollywood Heights, Beachwood Canyon, Laurel Canyon, Mount Olympus, Outpost Estates, Nichols Canyon, Sunset Hills and Flats, Hollywood Dells, and Whitley Heights. It is located in the Santa Monica Mountains and bound by Laurel Canyon Boulevard, Griffith Park and Mulholland Drive, Vermont Avenue, and Sunset Boulevard. The houses in the area are nestled into the winding hills and offer stunning views of the city below. Because of the way homes are built on the hills, it is considered a very private area, making it very attractive to a number of celebrities. The homeowner list in the Hollywood Hills has included Sandra Bullock, Ben Affleck, Reggie Bush, Kevin Costner, Christina Aguilera, Kathy Bates, Cameron Diaz, Leonardo DiCaprio, Madonna, George Harrison, Paris Hilton, and Harry Houdini. The most famous symbol of the Hollywood Hills area is the famed Hollywood sign. While the sign was originally nothing more than an advertising gimmick that did not quite work out as planned, it has become one of the world's most well-known landmarks, making it the subject of many preservation campaigns.