In the Bible, it says that there will a be a tree that will grow in only two places on Earth. These two places will be the place closest to the entrance to hell and the place closest to the entrance to Heaven. The Joshua Tree grows in Amboy. The only other place that it grows is Jerusalem.
Amboy is also where Charles Manson was born and raised and it's the place where he committed many of his murders.
Satanists gather there every Halloween to do whatever creepy stuff Satanists do.