The team that has been exploring the underwater city recently discovered off the coast of Cuba has released a bit more information. They sent a video camera down and found there are inscriptions on lots of the stones. The weather and water conditions plus some equipment failures have prevented them from getting a lot of good images but the site has taken on great archeological significance because of the images they have captured.
here's a link to the latest interview and some info about the possible cultural links to Etruscan and Mezo-American sites. http://www.earthfiles.com/earth303.htm