Royllo (also Roillo), is a legendary

phantom island A phantom island is a purported island which was included on maps for a period of time, but was later found not to exist. They usually originate from the reports of early sailors exploring new regions, and are commonly the result of navigati ...

that was once thought to be located in the

Atlantic Ocean The Atlantic Ocean is the second-largest of the world's five oceans, with an area of about . It covers approximately 20% of Earth's surface and about 29% of its water surface area. It is known to separate the " Old World" of Africa, Europe ...

. It is probably identical with the island originally called Ymana in a 1424

nautical chart A nautical chart is a graphic representation of a sea area and adjacent coastal regions. Depending on the scale of the chart, it may show depths of water and heights of land (topographic map), natural features of the seabed, details of the coa ...

Zuane Pizzigano Zuane Pizzigano (sometimes given as Giovanni Pizzigano), was a 15th-century Venetian cartographer. He is the author of a famous 1424 portolan chart, the first known to depict the phantom islands of the purported Antillia archipelago (Antillia, Sa ...

. The island is usually depicted in many 15th-century maps as a small island located slightly to the west (20 leagues or so) of the much larger island of

Antillia Antillia (or Antilia) is a phantom island that was reputed, during the 15th-century age of exploration, to lie in the Atlantic Ocean, far to the west of Portugal and Spain. The island also went by the name of Isle of Seven Cities (''Ilha das Se ...

.University of Minnesota, Twin Cities,
Armando Cortesão and Island Names
It is often found in the group ''insulae de novo repertae'', or "newly discovered islands" along with other legendary islands.

References

{{reflist Phantom islands of the Atlantic Mythological islands Pre-Columbian trans-oceanic contact