Even though the most famous underwater city of all, Atlantis, is probably a myth, there are a number of well-known submerged metropolises around the world. Some of these cities are well known to history, while others are mysterious and unexplained.
For most of human history, these communities were lost to view, but today diving equipment, robots, submarines, and underwater cameras bring them back to life. Today archeologists, tourists, historians, and others can visit and explore underwater cities much as they explore ruins or abandoned communities. Every day more and more underwater cities are giving up their treasures.
Here is a documentary named "Sunken Civilizations: Secrets of Lost Cities Underwater", from which you can visit some amazing underwater cities with the divers