A city constructed above Tokyo Bay after World War III destroyed Tokyo.
Neo-Tokyo is the fictional setting of the manga/anime Akira.
Tokyo became Neo-Tokyo when it was destroyed on December 6, 1992. Tokyo was destroyed by a powerful psychic boy named Akira. Neo-Tokyo is full of poverty, gang war, and violence. Two gangs that prominently rule the city are Kaneda Shotaro's gang "the Capsules" and their rivals called "the Clowns".
The City erupts in panic and chaos when Tetsuo Shima (another powerful psychic goes on a city wide rampage). Leading to the city being put under marshall law by the military.
Eventually Neo-Tokyo is destroyed once again by Akira who is resurrected to kill Tetsuo.