There was a 4000 meter tall pyramid city called X-Seed 4000 which was designed but was never meant to be built. [first picture on the left]
– Transport throughout the complex would be connected by an integrated 360 degree network (horizontally and vertically). Elevator cars that go up down and sideways.
– It could house one million people and be provide for all their food, water and energy needs inside the structure
– It would use 10% of land surface that a normal one million person city would need
Another rendered view of the Dubai Ziggurat