Hearst castle is not in Los Angeles. It's in San Simeon near the coast, 4 hours north of LA. It's a very historical castle rich with Hollywood history. William Randolph Hearst was one of the most wealthiest men in the country due to his success in newspaper publishing. He and his wife would invite Hollywood A-listers up to his castle every weekend (they traveled up to the castle on his private train), to partake in luxurious parties . The movie Citizen Kane, which is considered to be the best movie ever made, is based on the life events of William Randolph Hearst while he lived in this castle. I'm sure Gaga recognizes the history of this castle and will most likely make reference to it.