The «Ocean Turtle» (オーシャン・タートル, Ōshan Tātoru?) is a mega-float located in the Pacific Ocean, at a place near Izu Islands about 250 kilometres away from Tokyo, that is run by Rath and acts as a government research facility for «Project Alicization», an effort to create a highly adaptive Artificial Intelligence.
Funding for the facility was acquired from the government under the name of "Maritime exploration". Officially, it is supposed to be used as a facility for seabed oil extraction and research into AIs used for small submarines to navigate on their own, but in reality, it houses four Soul Translators (STLs) that are used for Project Alicization to develop the first «bottom-up» AI, which Rath plans to use for military purposes of updating Japan's weapon technology.
Officially, the ship belongs to the Japan Agency for Marine-Earth Science and Technology, but, as the construction was carried out with the co-operation of the Japanese Self-Defense Force (JSDF), its members are constantly aboard the ship, actively guarding it even after the construction was finished. Additionally, the main shaft that stabs through the hull's core is completely under the control of the JSDF and is the place where the top-secret Project Alicization is conducted.
The ship takes the form of a large, four-sided black pyramid with 2:3 ratio edges. The height of the facility is that of a 25-story building. It is 400 meters long and 250 meters wide, with large black solar power panels covering it like a shell. There are leg-like projections from all four corners, an animal face-like command bridge attached on one of the sides, and an H logo on the roof, designating a helipad. Due to its "shell", the ship looks like a turtle, while the command post looks like the "head" of a pig.
The Ocean Turtle is comprised of twelve decks. The 1st deck from the waterline is the floating deck, the 2nd is occupied by the engine room, while the 3rd to 8th comprise all kinds of research facilities, such as marine biology, deep-sea resources and plate tectonics. The 9th and 10th decks hold the cabins, the 11th is the recreation deck with the lounge, gym, pool and such, while the final 12th deck is where the radars and antennas are installed, as well as an observation platform.
The central area of the pyramid has a hollow round titanium alloy stabilizing pipe, called the «main shaft», that is twenty meters in diameter and 100 meters in height. This pipe acts as a pillar that supports every floor of the structure, a pressure bulkhead and also acts as a layer of protection for important research facilities. Within this pipe lies the main control systems of the ship itself, as well as the four STLs and the Light Cube Cluster. The main shaft is divided into the upper and lower shafts at its central area, which is a wall-like titanium compartment that houses the Light Cube Cluster. Above the compartment is the upper shaft, where the «Second Control Room» («Sub-Con») as well as STLs number four and five are held, and below the compartment is the lower shaft, where the «Primary Control Room» («Main-Con») and STLs number two and three are held. Moving from one shaft to another is possible via stairs or an elevator.
- The turtle-pig appearance of the Ocean turtle is a reference to the Mome Rath, a creature in Jabberwocky described as a turtle or a pig whose name the enterprise behind Project Alicization has taken.
- The inner areas of the Ocean Turtle are strictly air conditioned due to the intricate machines requiring a constant temperature of about twenty-three degrees Celsius and humidity under fifty percent.
- Although the shell of the Ocean Turtle is covered in numerous black solar panels, the energy acquired from them is not enough to fulfill even ten percent of the base’s energy requirement. Therefore, the main machines use a pressurized water nuclear reactor for electricity.