Per 
Item #: SCP-XXXX
Object Class: Safe
Special Containment Procedures: A 3m tall privacy fence is to be constructed around the property boundary of SCP-XXXX. Unstable structure signage is to be placed on all four sides of the perimeter fence to deter public suspicion. Mobile Taskforce CHI-1 (Aka "Outliers") Are tasked with protecting the site from trespassers and are to be stationed within a three-block radius around SCP-X in suitable plain-clothed attire. Two members of CHI-3 are to be posted to watch the aperture of SCP-X at all times to safeguard against any SCP-X-1 instances that may come through.
Any persons that breach the boundary of SCP-X are to be apprehended and administered amnestics before being released. Any staff desiring to enter SCP-X for research purposes must have level 3 approval.
Description: SCP-X is a stable rupture in the space-time continuum measuring approximately 2m in radius and is housed inside an abandoned warehouse. SCP-X is traversable, and leads through time and space to an underground city called "Last bastion." Records retrieved from this city indicate that the approximate year on the other side of SCP-X is ████, and claims to be the last human city on earth. This city seems to be capable of housing three-hundred thousand people and appears to have been inhabited at a previous time, as various possessions and personal effects have been found inside the homes. However, exploration of the city has so far found it devoid of any human or other presence, no reason for the abandonment of the city has been made clear as the city infrastructure is still intact, air and water filtration is functional.
Last bastion is located 7,500 feet below the surface in what has been identified in our current time as a goldmine in ██████.
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