I was just there a few weeks ago. When we toured the Iolani Palace, we were so surprised to learn that some scenes in Hawaii Five-O were filmed at the Palace. One example is the opening credits when Jack Lord turns around and looks toward the camera. He's standing on the veranda of the palace. They said that some things were also filmed inside the palace. That surprised us most. I think they said that the exterior of the palace is what was shown as being the headquarters where McGarrett's office was supposedly located.