When James Cook thought he had discovered Australia and claimed it for the crown in the 18th century, he was late to the party. Another English explorer had been decades ahead in sighting the great southern land, while Dutch explorers had been charting the continent even earlier.

But evidence has emerged to suggest that neither the English nor Dutch were the first Europeans to reach the continent during the great era of epic sea adventure and global circumnavigation.



©National Library of Australia
The 1547 chart said to be based on a Portuguese voyage to Australia in the 1520s

A set of maps unearthed in Australia appear to show that Captain Cook was predated by a little known Portuguese explorer, Cristovao Mendonca, who charted parts of the coastline 250 years earlier. Drawn in the early 16th century, the charts bear a close resemblance to Australia's coastline, and this coastline is marked with locations given names in Portuguese.

An Australian journalist, Peter Trickett, claims he stumbled on the hand-crafted documents while browsing in a Canberra bookshop eight years ago, and says they are an accurate depiction of headlands and bays along the east coast, thus proving that Mendonca navigated the area in the 1520s.

"It was so accurate that I found I could draw in the modern airport runways, to scale in the right place, without any problem at all," he told Reuters, adding that he could recognise all the headlands and bays around Botany Bay. Mr Trickett has published his findings in a book, Beyond Capricorn.

The maps apparently were drawn by French cartographers from a series of portolan maps, or rough navigational charts, either captured from the Portuguese or bought secretly.

However, some academics dismiss the claim that they represent Australia. Several describe a place called "Terra Java" which bears strong similarities to Australia's coastline - except that, at one point, it juts out at right angles for more than 900 miles.

Mr Trickett says this may be because the portolan fragments had not been assembled in the correct way.

"There was something familiar about them, but they were not quite right," he said. It occurred to him that cartographers in France looking at the Portuguese charts may have become confused. Putting together the portolan charts, many drawn on animal hides, would be a bit like composing a jigsaw puzzle. "Without clear compass markings, it's possible to join the southern chart in two different ways," he said. "My theory is, it had been wrongly joined."

Mr Trickett used a computer to play with the maps. When he rotated part of one map 90 degrees, he ended up with a picture that fitted Australia's east coast. The redrawn map, he says, shows a stretch of eastern Australia from Kangaroo island, near Adelaide, to mainland Australia's southern-most point at Wilson's promontory and up the east coast to Botany Bay, Sydney and beyond.

"They provided stunning proof that Portuguese ships made these daring voyages of discovery in the early 1520s, just a few years after they had sailed north of Australia to reach the Spice islands, the Moluccas," he said. He believes the original charts were made by Mendonca after he had set sail from the Portuguese base at Malacca with four ships on a secret mission to discover Marco Polo's "Island of Gold" south of Java.

With Spain and Portugal vying for control of the world's oceans and territories being discovered, both kingdoms kept maps and charts locked up. Many Portuguese maps were lost for posterity when the repository, the Casa da India, in Lisbon was destroyed by an earthquake in 1755.

Australians have long speculated over other clues that point to a European presence well before the British: the remains of a so-called "Mahogany Ship", supposedly discovered on a beach in the 19th century but since lost. The vessel was said to be "dark, hard wood" made "after the fashion of a panelled door". This, say proponents of the Portuguese claim, may be a caravel, or galleon, lost by Mendonca during the voyage.

Some even suggest that the British, when they set out to find Australia, knew Mendonca had been there, and provided Captain Cook with copies of the Portuguese charts.

Mr Trickett believes Mendonca's feat warrants him a place alongside Christopher Columbus and Ferdinand Magellan. If he is right, then Captain Cook failed in his stated quest to go "farther than any man has been before me". Yet he remains the European credited with finding Australia, and statues of him can be found as far apart as Greenwich in London, Hawaii, and Victoria in Australia.

Mendonca, on the other hand, retired to run a fort in what is now Iran, and his exploits remain but a footnote in Portugal's rich history of navigation and discovery.