The Hydropolis Underwater Hotel and Resort is a proposed underwater hotel in Dubai. Hydropolis should be the first multi-room underwater hotel in the world. It was planned in the Persian Gulf off Dubai through the mediation of Hans Peter Pesenhofer following plans of Siemens IBC (Prof. Roland Dieterle) in cooperation with the German Designer Joachim Hauser and with the approval of the DDIA. The hotel's original plan was to be located 20 meters underwater off the coast of Jumeriah beach. The hotel's plan is to cover an area of 260 hectares, which is equivalent in area to Hyde Park in London. The construction cost for Hydropolis is approximately € 600 million Euro, which will make Hydropolis one of the most expensive hotels ever created. The hotel design was created by Joachim Hauser and Professor Roland Dieterle, and is planned to be composed of three segments: a land station, a connecting train, and the underwater hotel. Joachim Hauser's and Prof. Roland Dieterle's architecture idea is to represent the connection between humans and water.