July 7th, 1987, I dived to a depth of 3,100 m (~10,100 ft.) in the submarine Alvin. Yes, that's the sub that found the Titanic just two years earlier in 1985. I went diving with Patty Fryer to the Kasuka 3 seamount north of Saipan in the Mariana region of the Western Pacific. This was thought to be an old volcano, but it could have been what is called a "mud volcano", which forms when the descending ocean plate loses its water that then rises to the surface again, bringing lots of sediment with it. Much of this Gallery shows surface operations, because I only dived once. And when you are underwater (for eight hours in my case), it is usually very dark both inside the sub (to save batteries) and outside (as there is nothing to see). Only the four hours on the bottom did we use flood lights, and then the batteries were only able to illuminate the bottom for a few tens of meters around the sub. The overall feeling was that we were exploring an alien world!