After it was abandoned around 1400 due to its conquest by the Aztecs, the city of Zapultepec wasn’t discovered and excavated until 1930. The statuary was long sunk into ruin, but there was one fascinating artifact that mystified its discoverers and continues to excite speculation to this day.
A cube, rough and not perfect, but seemingly made of stone. Bizarrely, it appeared to be made out of steel-reinforced concrete with heavily pitted and rusted rebar sticking out in several spots. This was particularly impossible, as steelmaking did not exist in pre-Columbian Mexico, and steel-reinforced concrete in particular was not invented in the form of the cement cube of Zapultepec until 1884.
More bizarrely still, the cube seemed to have fallen to the Zapultepec site from a great height, at least 300 feet if not more than 1000. This was evident in the strata and ejecta of the impact, still visible after hundreds of years. But is it was impossible for rebar-embedded concrete to be there, it was doubly so for it to have fallen from such a great height.
Largely thanks to the cube, Zapultapec’s otherwise unspectacular ruins have become a tourist attraction. It’s cited by many in paranormal circles as a prime example of an OOPART, an out-of-place artifact that demonstrates that some form of time travel or alien intervention has taken place.
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