Zion (The Matrix)

Zion is a fictional city in The Matrix films. It is the last human city on the planet Earth after a cataclysmic nuclear war between mankind and sentient machines, which resulted in artificial lifeforms dominating the world.

Following the United Nations attack upon the newly established machine civilization of Zero One, a global nuclear war between both factions began for control of the Earth. After several desperate plans to halt the seemingly never-ending waves of robot-soldiers, the human leaders realized that the Machines had a good chance of winning. The human leaders began the construction of an entirely underground city, called Zion, that was built for the purpose of preserving the human species. When the war ended in the Machines' favour, the remnants of humanity were left struggling to survive on the cold, dangerous, and desolate surface. It was quickly becoming uninhabitable due to the cloud created by Operation Dark Storm. The Machines captured or killed almost all humans with the exception of the inhabitants of the unfinished Zion. The captured survivors were imprisoned and put into the newly constructed bio-electric towers with their minds placed in the Matrix to keep them docile. Twenty-three prisoners (sixteen female, seven male) were freed by a mysterious Matrix-controlling figure referred to as "The One" and led to the unfinished Zion where they worked to complete it. After making the city operational and regaining technological usage from geothermal energy from the Earth's core, the One taught the humans to continue building and maintaining a war effort, and to fight inside and outside the Matrix. After the One's death, the humans learned to survive on their own and began waging a partial-guerrilla war from Zion against the Machines, and at the same time trying to free the Matrix's population from their virtual "prison".

Zion was built four kilometers below the Earth's surface, just above the Earth's mantle, and exists entirely underground. The city itself is cylindrical (vertically inclined with respect to Earth's surface) in design and possesses many levels including:

Zion has a multitude of defensive systems that collectively is commonly known as the Zion Defence Grid. The systems consist of:

EMP devices, despite being installed on every hovercraft in the fleet, were never installed in Zion's defensive grid (even as a last resort), primarily because the city possesses no EMP shielding. Though an EMP could be used and every Machine in its range instantly disabled, the defensive grid, APU fighters and virtually every piece of defensive hardware in Zion would be permanently disabled as well, leaving the city with no way to defend itself during a second Machine incursion.

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