Gobekli Tepe really fascinates me. The problem with a lot of these ancient civilizations is most of them are under 400 feet of ocean.
Many times in the past they were not as you know. Marine archaeology is a field that needs more investment for sure. The find off the coast of Cuba has me very curious, but they are squashing any exploration or possible findings from that one. But there are some strange things around Cuba that can even be seen using google earth.