PURPOSE: To provide an environment at the bottom of the sea suitable for diving besides characteristic functions of an artificial rocky place under water where fishes tend to gather.

CONSTITUTION: A main body 2 of a rocky place under water where fishes tend to gather, for example, has structure wherein the interior of a frame 3 made of a steel is packed with a great number of bulky stones 4. A model 5 of a building structure is set at the top of the main body 2 of the rocky place under water where fishes tend to gather. A statue or artistic handicrafts are arranged instead of the building structure. The part of the main body 2 of the artificial rocky place under water where fishes tend to gather works as the rocky place of its own. The upper building structure 5 creates a spectacle rich in changes suitable for a diver to walk the bottom of the sea. The lower main body of the rocky place raises value as a diving spot in corporation with gathering of fishes.