California as an Island

The Island of California is one of the most famous cartographic errors in history. It was a long held misconception that Baja California was separated from mainland North America by the Mare Californica. The first known mention of this legend was in a 1510 novel by Garcia Ordonez de Montalvo who described the island in this passage: Know, that on the right hand of the Indies there is an island called California very close to the side of the Terrestrial Paradise; and it is peopled by black women, without any man among them, for they live in the manner of Amazons. It is probable that this description prompted explorers to misidentify Baja California. In 1539, Hernan Cortes, sent Francisco de Ulloa in search of the island. Ulloa's expedition, as well the expedition of Hernando de Alarcón the following year, proved that Baja California was a peninsula. Maps published in Europe, including those by Gerard Mercator and Abraham Ortelius, correctly showed California as a peninsula. In 1592, Juan de la Fuca reported the existence of large opening on the coast of North America that possibly connected to Atlantic Ocean, providing the route for the Northwest Passage. In 1602, Sebastian Vizcaino navigated the California coast with Father Antonio de la Ascension, who wrote a journal of the voyage describing California as separated from the mainland. The first appearance of the Island of California on a map dates to 1622 on a map by Henry Briggs, this became standard for maps throughout the seventeenth century. In 1705, the Jesuit missionary Father Eusebio Francisco Kino proved that Baja California was a peninsula by walking from New Mexico to California. Subsequent maps in France began to display California correctly as a part of the mainland, but mapmakers in Netherlands, Germany, and England continued to propagate the error until the mid 1700s. In 1747 Ferdinand VII of Spain issued a formal decree that California was a part of the mainland.

Rupes Nigra

Rupes Nigra was believed to be an island of black rock, 33 miles wide at the North Pole. The idea came from a lost work titled 'Inventio Fortunata', a work written by a 14th century monk. It described the North Pole as four countries that surround a whirlpool into which four seas empty into the earth as through a funnel. Right under the pole in the midst of a sea lay a bare magnetic rock, Rupes Nigra. The Island features on maps from the sixteenth and seventeenth centuries.

Frisland

Frisland was a mythical island that appeared on almost all maps of the North Atlantic from the 1560s through to the 1660s. Nicolo Zeno, a descendant of the Zeno brothers, published a map in 1558 in Venice purported to have been from around the year 1400 when his ancestors supposedly undertook a voyage and crossed the Atlantic. On the map appeared many non-existent Islands, one of which was Frisland. Frisland continued to appear on maps for the next 100 years and was shown with detailed coastline and named harbours. Frisland eventually came to be identified with the Faroe Islands.

Bacalao

Bacalao was a mystery island on several sixteenth century maps. It is often used to name Newfoundland as well as the phantom Island. Shown here Bacalao is used to name land (Terra de Bacallaos) and an Island (Y Bacailo). The name was first used on a map in 1508 and the Portuguese navigator Joao Vaz Corte-Real was granted land on the Azores due to having discovered Terra do Bacalhau. Bacalao also means codfish and Basque fisherman are said to have fished on cod at the Grand Banks of Newfoundland in the 15th century, so this could also explain the origins of the name.

Pepys Island

Pepys Island was said to lie about 230 miles north of the Falkland Islands. It was first described by Ambrose Cowley in 1684, presumably mistaking the coordinates of one of the Falkland Islands, and named by him for Samuel Pepys. Many expeditions attempted to locate the island during the eighteenth century. Explorers such as Louis-Antoine de Bougainville, Lord Anson and even Captain Cook continued searching for Pepys Island until the 1780s, when Cowley's original journal was rediscovered and his mistake noticed. Herman Moll went as so far as to put an inset of Pepys Island on his map of Chilli. 

Aurora Islands

The Spanish ship Aurora first reported a group of three Islands in 1762 whilst on a voyage from Lima to Cádiz and subsequently named them the Aurora Islands. In 1794 they were recorded once again by the corvette Atrevida, which had been sent to find them. Their location was East of Cape Horn, approximately half way between the Falkland Islands and South Georgia. The islands were last sighted in 1856, and are now regarded as mythical. They continued to appear on maps of the south Atlantic until the 1870s. This map denotes that Captain Thayen saw the Islands in October 1825.

St Brendan's Isle and Brazil

St. Brendan's Isle was named after Saint Brendan who founded the Clonfert monastery and monastic school. The first mention of the island was in the ninth century Latin text 'Navigatio Santi Brendani Abatis' (Voyage of Saint Brendan the Abbot). This established the Island in Irish and European folklore. It was appeared on maps at the time of Columbus and may have been of influence to his journey. The island was apparently discovered by the saint and his followers while they were sailing about Northwest Europe spreading the Christian faith. It has sparked some controversy, because the claim is that St. Brendan and his brethren arrived at the Americas first, around the 6th century.
Brazil is a phantom island which also features in many Irish Celtic myths and probably has similar roots to St Brendan's Island. It was said to be cloaked in mist, except for one day each seven years, when it became visible but could still not be reached. Several expeditions left to search for it in the late fifteenth century, the last led by John Cabot. The last supposed sighting being in 1872, but it appeared regularly on maps lying south west of Galway Bay from 1325 until 1865, by which time it was called Brazil Rock. The island is shown as circular, with a central strait or river running across its diameter.

Korea as an Island

Korea was first shown as an Island on the Abraham Ortelius' Japan Insulae. Luis Teixeira, a Portuguese cartographer to the court of the Spanish King, sent Ortelius two maps of China and Japan, which were based on unknown sources as Teixeira had not visited Japan. There is deliberate hazing at the top of Korea as if to demonstrate the ambiguity of the information and on the Hondius map there is a note in Latin that Korea might not be an island. However, other cartographers chose to separate Korea completely from the mainland as shown here.

Isle of Demons and Mayda

The Isle of Demons was once believed to exist near Newfoundland. It began appearing on maps in the beginning of the 1500s, and disappeared at the end of the seventeenth century. Legend was that demons and wild beasts populated the island. These creatures would torment and attack any ships that passed or anyone foolish enough to wander on to the island.
Mayda was a fictitious island that was shown on several different maps, its last appearance on a 1906 Rand McNally map. It is often represented in the shape of a sickle and its position has varied widely during over time. Early maps put the island Southwest of Ireland and it later it moved towards The Americas. It is thought that its purpose was to fill empty spaces on maps.