Mankind over time lost one or another item to the sea; mostly ships and airoplanes, and archeologists are happy when they recover more or less well-preserved specimina. Well known examples are f.e. the Vasa (Ger., Eng.) (sent to the bottom by a devious gust of wind on her maiden voyage on 10th of August 1628), the Oseberg ship (Ger., Eng.) (here‘s a list of other historic Norwegian ships and boats), or the Brandtaucher (Ger., Eng.), the first working submersible of the Reichsflotte. Divers enjoy more or less the visit of wrecks and some of them – wrecks – are notorious and well know today, especially in areas where scuba diving is a touristic amusement and offer, f.e. in the Red Sea. The SS Thistlegorm shall be mentioned representative for others.
But diving is hard work and having a resting place at hand would be nice, why not built a house? Through the 1950s and 1960s underwater stations were constructed, tested and used, serious scientific research was done. Most of these stations were movable and in fact were removed after having served their purposes. As I see it only Jules’ Undersea Lodge was kept and transformed into a kind of hotel. The only active and regularly used undersea research station today is AQUARIUS Reef Base. The undersea laboratory is owned by the National Oceanic and Atmospheric Administration (NOAA) and managed by the University of North Carolina at Wilmington (UNCW). (The NOAA has also an interesting collection of photographs.)
Historical undersea habitats are listed in the Habitat Archive, sadly the English page does not to work but it is a starting point. The 1969 SEALAB III seems to have reached the deepest point with more than 180 meters, tragically a deadly accident occurred and the project was ceased. But not only the Americans did research in this field, Europeans too were interested in the underwater possibilities. The 1968 German station HELGOLAND today can be visited in the Nautineum departement of the Deutsche Meeresmuseum. But all these devices are closely related to submarines, they are moving, transport their crew to the bottom of the sea, shelter them there and bring them back – in a way they are giant decompression chambers (Ger., Eng.).
I think besides JULES’ aforementioned Sea Lodge only Jacques-Yves COUSTEAU (Ger., Eng.) built lasting structures under the surface of the sea, the remains can be visited still today. The projects CONSHELF or PRECONTINENT I to III were realized 1962 near Marseilles, 1963 in the Red Sea and 1965 near Nice. The remains of 1963 are still visible (examples here and more here, beware pics are free to look but not free to use!).
The French seem to have a special relation to the sea and embrace modern technical possibilities, but whether the SEA ORBITER will ever drift across the oceans may at least be questioned – I am admittedly a complete bloody layman regarding technical things. Other ideas include floating homes, interesting cliff houses and landscape design – whether it will look like this?
I myself will not swim to look at COUSTEAU’s crumbling ruins in shark infested waters, but would like to sit in the Red Sea Star and work my way through the bar. Is there a drink called Calypso?