Cases that remain genuinely open, with the evidence laid out and the speculation labelled as speculation.https://worldofcurious.com/en-auhttps://worldofcurious.com/article/the-stone-spheres-of-costa-rica/https://worldofcurious.com/article/the-stone-spheres-of-costa-rica/More than 400 carved stone balls, some weighing 26 tonnes, made by hand over a thousand years ago. We know who made them and roughly how. Nobody can say why.Fri, 18 Sep 2026 23:00:00 GMTUnsolved Historical Mysteriesarchaeologycosta ricamysteriesunescopre-columbianEditorial Teamhttps://worldofcurious.com/article/the-manuscript-nobody-can-read/https://worldofcurious.com/article/the-manuscript-nobody-can-read/A 240-page medieval book written in an unknown script, illustrated with plants that do not exist. Here is what is actually established about it, and what is not.Sat, 12 Sep 2026 21:00:00 GMTUnsolved Historical MysteriesmysterymanuscriptshistorycryptographyEditorial Team