Case file · High strangeness
San Borondón, the phantom island
After repeated sightings of an island west of La Palma, the Captain General of the Canaries sent the last official expedition to find San Borondón in 1721; it found only open sea.
1721 CE · 28.10, -18.50 · status: disputed
The account
The 'eighth island', named after the Irish monk Saint Brendan, appears on maps from the Middle Ages and was sought by expeditions from the 16th century on. Sightings and even photographs continued into the 20th century.
The sceptical view
Explained as mirages (fata morgana) or cloud banks on the horizon that look like an island at certain hours.