More evidence that our ancestors were not stupid:
Where and how did medieval mapmakers, apparently armed with no more than a compass, an hourglass and sets of sailing directions, develop stunningly accurate maps of southern Europe, the Black Sea and North African coastlines, as if they were looking down from a satellite, when no one had been higher than a treetop?
The earliest known portolan (PORT-oh-lawn) chart, the Carta Pisana, just appears in about 1275 — with no known predecessors. It is perhaps the first modern scientific map and contrasted sharply to the “mappamundi” of the era, the colorful maps with unrecognizable geography and fantastic creatures and legends. It bears no resemblance to the methods of the mathematician Ptolemy and does not use measurements of longitude and latitude
And yet, despite its stunning accuracy, the map “seems to have emerged full-blown from the seas it describes,” one reference journal notes. No one today knows who made the first maps, or how they calculated distance so accurately, or even how all the information came to be compiled.
“The real mystery is that if you took all the notebooks from the sailors used in making these charts, along with the coordinates and descriptions,” Hessler says, tapping the glass that covers the ancient vellum, “you still couldn’t make this map.”
The article reports on research using high-tech mapping technology that proves just how accurate these ancient maps were.