Per 
Item #: SCP-5159
Object Class: Safe
Special Containment Procedures: SCP-5159 is known to the local town of [REDACTED], however it is believed to be a place of great evil by the people and none have ever been to the site. We are undertaking a misinformation campaign regardless to provide added concealment and amnestics are being held on standby if needed. SCP-5159 itself requires no intensive containment procedures. Only a small guard unit to deal with any unauthorized personnel that may attempt to investigate the site.
Description: SCP-5159 is a fortress located in [REDACTED], Africa. It is unknown what civilization constructed it as the architecture does not resemble that of any human civilization currently known to exist. The entire structure is composed of contiguous slabs of blackened quartzite. Chemical analysis was inconclusive on the cause of this blackening. Radiometric dating place its age at 13500 ±300 years.
Construction: The fortress consists of a 200m diameter hexagonal curtain wall, 6.5m tall, 4.23m thick with 20m obelisks at each point. At the top of the hill in the center, up a long, winding path sits the main structure of the fortress. The structure resembles a flat-top pyramid with a slope of 13.3 degrees, the walls have 5cm indentations at 20cm increments. On the Northern face, what initially appeared to be a black void turns out to be some kind of gate. It is composed of a strange material that absorbs all light, hence appearing completely black. All attempts to retrieve a sample have failed as the material is impervious to our tools.
20th December 2019
Ground penetrating radar surveys of the site have revealed extensive webs of some unknown and potentially exotic material. The material seems to completely absorb or deflect electromagnetic energy. At 20m down a large amount of this material pervades the entire site and 500m from the center. It may be similar to the material the gate is composed of. More testing is to be performed to evaluate. Moving to perform seismological analysis of the site which may reveal more properties.
24th December 2019
Seismological analysis has revealed that the material is 12.78 ±0.05 times denser than granite. The material at 20m is consistent with the ground penetrating radar results. It has also revealed that the layout of the underlying structure seems to change. We have now set up seismic activity monitoring devices in an attempt to record how often this occurs.
25th December 2019
Testing of the gate has shown that the material does indeed possess similar properties to the material beneath the site. It absorbs all wavelengths and energies of EM up to and including gamma rays.
11th January 2020
The 'gate' has been confirmed to be a gate since it has now opened for an unknown reason. A team is being prepared to enter SCP-5159.
12th January 2020
Personnel have been reporting experiencing radio interference while in the vicinity of SCP-5159. Analysis revealed that the site is emitting radiation up and down the radio wave region of the EM spectrum. Currently these emissions appear to be completely random we are nonetheless collecting the data and running it through machine learning algorithms in an effort to decipher any meaning.
13th January 2020
The research team has advised that animal subjects be used before humans to ascertain the safety of the interior as SCP-5159 has numerous strange anomalies of a EM nature.
14th January 2020
Animal subjects have entered inside SCP-5159, requiring a high level of coaxing to do so. They seem to have an instinctual aversion SCP-5159
16th January 2020
Preliminary investigation of the interior of the main structure is proving to be potentially hazardous to life. Animal subjects that entered SCP-5159 have failed to return.
