"Polish company Deep Ocean Technology thinks tourism is the way to make the [underwater cities] economical. It has signed deals with architects and builders to deliver the Water Discus Hotel at the Noonu Atoll, Kuredhivaru Island in the Maldives within three years. The company is also involved in discussions about building hotels under the waves in Dubai, Singapore and more than one European location, including in Norway."
http://www.bbc.com/future/story/20130930-can-we-build-underwater-cities
http://www.bbc.com/future/story/20130930-can-we-build-underwater-cities