The rocks are individual solids each created from scratch. Jacuzzi in the middle of the cave with a walk in entrance from the back right side and through middle of pool. Pool bar is recessed to be level with the people in the pool. The whole on the top of the rocks in the middle of the lounge area is a opening for skylight that is straight above the Jacuzzi. And yes the fin that you see in the middle of the water in the pool is a shark's fin. There is a whole shark there and that is a solid as well. Everything in this model is an individual solid create from scratch. Thanks for looking and hope you enjoy because I know I did!