Caesarea has a theatre, not an amphitheater because it is only a half circle.
The entertainment was an all day event, and they used pulleys to draw canvases across to block the sun.
The misfit pieces of marble you can see on the floor are original pieces!
The curved out pieces in front of the stage are places larger string instruments were played, using the curved walls to help amplify the sound with the rest of the orchestra.
The dungeon looking picture is where the dressing rooms are below the stage!
The arches were a famous invention, splitting the weight between both sides so buildings could be built in stories. He did this at the amphitheater, the palaces, and the temples.