For a few hundred years, maps of the world included the island of San Juan, lying just off the coast of north-eastern Mindanao.
Atlases of the 16th to 18th Centuries even included descriptions of the island's inhabitants, who were said to be taller than the average Filipino, with thick, black curly hair.
Cartographer Christopher Middleton, for example, gave a detailed description of the islanders in his A New and Complete System of Geography, which was published in about 1780. Indeed, the islanders were chosen as the subject one of the book's 24 illustrations.
San Juan also featured in maps by Sir Robert Dudley (1646), Jan Janssonius (1656), Vincenzo Coronelli (1690) and Jacques-Nicolas Bellin (1750), to name but a few.
But then, suddenly, San Juan suddenly ceased to be.
Of course, the boringly rational explanation is that the island was a simple error, perhaps caused by a geographer mistaking a river delta for an isthmus. Mistakes such as this are readily passed on as new mapmakers consult old sources.
But where's the fun in that?
So, perhaps the island went the way of Atlantis, destroyed by angry gods for its debauchery and pride?
Well, no, that theory doesn't work. When the Indonesian island of Krakatoa was destroyed by a volcanic eruption in 1883, the effects were noticed as far away as Europe. Such a cataclysmic event would have been noticed.
Or, could it be that the island still exists, but is somehow hidden, like Wakanda of Black Panther fame?
There is a precedent for a such a realm in the Philippines, in the form of Biringan City. Located in Samar, this invisible settlement is said to be inhabited by the Engkantos (“enchanted beings”) and their half human progeny.
According to Wikipedia, the supposed location of Biringan City once showed up on satellite images as somehow “brightly lit”. This led a japanese company to believe there were rich deposits of gold and uranium in the area.
They then set up an operation in the nearby town of San Jorge to mine these valuable resources. However, a series of mysterious accidents and mishaps plagued the project from the start, forcing the firm to cut its losses and leave.
Also, it's worth remembering that the terrain of the Philippines is such that a single Japanese soldier could evade capture for decades after World War Two.
So, could an island, inhabited by unusually tall and sturdy people, somehow have found some sort of technology to remain hidden from the world?
Probably not, of course, but it's a compelling pipe-dream and would make a great movie!
For a more scholarly account of this cartographical conundrum, click here.
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