Busan, South Korea, will have a floating city prototype. The city will be constructed on concrete platforms that trap air to stay afloat. Underwater parts of the platforms will attract marine life and produce coral reefs. The prototype for the floating metropolis can shelter 12,000 people, but the modular platform might hold 100,000. When enlarged, the platforms will resemble honeycombs. The team intends to implement the city-planning approach on land.