Why the North Pole looked like this on Old Maps

Check out this map of the Arctic from the 16th century. There are four major land masses surrounding a polar sea with a massive magnetic rock in the center, called Rupes Nigra the Latin words for Black Rock.
Book Sources
-----
“The Phantom Atlas” - Edward Brooke-Hitching
"Half Moon" - Douglas Hunter
"A New World Voyager" - Edward Butts
RareMaps.com Sources
-----
1596 Geradus Mercator Arctic Map - www.raremaps.c...
1590 Petrus Plancius World Map - www.raremaps.c...
1570 Ortelius First World Atlas - www.raremaps.c...
Social Media
-----------------------
Map Shop - thegeographygee...
Instagram - / thegeographygeek
Patreon - / geographygeek