Medieval mapmakers sometimes drew sea monsters in unknown regions as a warning to sailors.

The longer version

Early charts filled empty spaces with decoration and warning. Where sailors had not returned from, mapmakers had no data, and a drawing of a creature served as a visual note that the area was dangerous or simply unknown. Blank space on a costly chart looked like an unfinished job.

Serpents, whales and dragons appeared alongside stories about currents and whirlpools. Such images also made a map more attractive to wealthy buyers. Latin wording sometimes accompanied them, roughly meaning that monsters live there, and it reflected uncertainty rather than belief in every creature drawn. As surveying improved, the pictures gradually gave way to soundings and coastlines.

Where this entry sits

These facts wander across maps, borders, deserts, rivers, mountains, and the extreme corners of the natural world. Each one is short and self-contained, offering a small surprise about places you may never visit rather than anything you actually need. The full list sits on the Geography page, where every entry is listed in order.