-yeah, i believe there are more than 6Oops, looks like this should actually be the new topic. But not sure if I fully understand this topic. Are there really six of these? Ships / spaceships that are also submarines?
-but anyway, this is a topic of mostly submarines!!
-but it could also be MOVABLE underwater bases/ship
-the underwater base in "the deep blue sea (samuel l jackson" movie, would NOT qualify
-thats a FIXED underwater, concrete, submarine base