This is a cavern chamber with water. On the top there is a hole that provides a source of visible light (lighting example in the scene). On the side there is a hole where you can add a corridor that would lead to the cavern (You can close it if you want). The water is animated by default.
All the rocks, walls textures are made with displacement maps. Provided in the zip. Many things can be added into the scene, like rocks and vegetations but since it would involve plugins, I have refrain of putting smaller objects.