It’s not the most well-organized museum you’ll find in Mexico, but what it houses proves to offer far more than morbid novelty.
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Many of the mummies are said to have perished in a cholera outbreak here in 1833, though, due to rigorous taxes placed on keeping bodies in the limited local cemetery space, bodies are continually being dug up and appropriated by the museum, though only a fraction are ever on display. If one desired to become a mummy, your best bet would probably be to die in Guanajuato and simply wait a while. Sooner or later, you’d have a good chance of winding up in here. The mummies of Guanajuato—amongst them the smallest mummy in the world!—are one of the most uncanny manifestations of Mexico’s obsession with death, a strange conspiracy between the elements, the folklore and the tourism industry.
For official, albeit brief, details about the Las Momias museum see the museum's page on the city's website.