Columbus was certainly not the "discoverer" of the americas, that notion was really abandoned quite some time ago.
It is generaly accepted that columbus was not the first european to come to the new world. But what columbus was the first at, his expaditions were
the first state sponsored attempts at exploration and colonization.
Its a certainty that the norse penetrated much farther into north american than in presently accepted.
These parties of only a few men would have left a very small footprint, almost undetectable.
Like JC says ,from larger base camps like L'ans aux Meadows, they set out on small scale trips, trips to fish for salmon and for fur hunting.
The fact they didnt stay has more to do with climate than anything else.
When they first arrived in NA in the 9th century, they had favorable seasonal winds and currents that made the journey fairly easy.
But as the 13th century approached the change in the climate ,meant what was once a seasonal journy of somthing like 3 weeks now took more than two
months and longer for the return.
Supplies got harder to get and good harder to return for trade with the home land.
Eventually the supplies stopped altogether and the settlements failed.
I had an early american history class that centered on early explorations of north america previous to columbus.
My professor assembled information on a small number of sites in NA that seem to indicate a deep level of penetration into the interior of north
america, by several european peoples including the irish and possibly the basque.
including these two examples of norse explorations
In 1931 a railroad brakeman named James Edward Dodd found a broken sword and fragments of an axe and shield near Beardmore Ontario east of Lake
Nipigon. Upon extensive examination, European Norse experts agreed that the relics were authentic Norse weapons.  Similarly, an artifact called the
Kensington Runestone was unearthed in 1898 by a Norwegian-American farmer in West-Central Minnesota. Now residing in a Minnesota Museum, the stone
carries an inscription that depicts an attack on a party of Goths and Norwegians that took place in 1362. The authenticity of this artifact is in
" target="_blank" class="postlink" rel="nofollow"> tripatlas.com...
The kensington runestone
A new piece of the runestone puzzle has added yet another layer of mystery.
Recently[when?], an authentic rune was discovered in a 13th century document that was identical to one of the unusual runes on the Runestone,
which linguistic experts had suggested was invented by a hoaxer. In response, Wolter examined each individual rune on the Kensington
stone with a microscope. He found a series of dots engraved inside four R-shaped runes. Research found that identical dotted runes are found only on
14th century graves in churches on the island of Gotland off the coast of Sweden. Wolter considered this proof of the runestone's authenticity.
The stone says it was a party of norse and "goths" and it has a rune specific to 14th century gotland.
That combined with the 14th century sword and sheild in quebec makes a pretty good argument.
We also discussed a japanese manuscript (12th -13th century?)that seems to describe a journey by buhddist monks to the west coast of north america,
well before the documented journeys of the 15th century to central and and rumored 17th century trips to south america.
In the monks account they sailed from japan with the rising sun on their right, for many weeks they sailed north, past the lands of the barbarians
(the Ainu) into a land of dark skys fogs and stormy seas.
After a long and arduous voyage they came to realize that the rising sun was now on there left, they were headed south.
As they sailed south the land grew more hospitable and warmer.
They past many different tribes of "ainu", they used the same word to describe both the ainu and the natives.
After quite some time they found themselves sailing along the coast of vast and unpopulated desert, the likes of which no japanese could even
imagine, coming from the wettest temperate region on the planet.
Agian they sailed for many days until one day after rounding a cape the rising sun was again on the right.
They sailed north till they entered the delta of a large and muddy river.
They sailed up the river till they reached a small settlement of "ainu".
Here they put in and set up camp, the locals were at first frightend of the strangers in the boats, but it didnt take long for them to realize that
the strangers were no threat.
they were able to communicate with hand gestures and crude pictures drawn in the sand.
From these locals they learned that there was a larger and more powerful tribe farther up the river, that lived in houses with roofs, not the
temporary saltbrush and willow shelters these people did.
They made/traded for some canoes and went up river for a short time (2 weeks) before they came to the first village of mudbrick houses.
They stayed with these friendly people for a fair amount of time, before returning down river to the rest of the compliment.
They stayed for a cycle of seasons (1 year?) before returning home.
There was also a voyage in the 15th century to central america that returned with samples of cotton cloth and pineapples.
Whats interesting is that peru was the first country to make formal diplomatic relations with japan in 1870.
And while I was in highschool (1980) a pair of chinese anchor stones were dredged up from long beach harbor.
They were of a style used in the 15th century, they were immediately dismissed as being dropped by a chinese ship in the 19th century.
the chinese treasure ship voyages led by Zheng He
The real Sinbad
Travelled all over the east and indian ocean and my have journeyed into the atlantic and maybe to the americas as is claimed by Gavin Menzies.
Although he is strongly disagreed with in the historical community, it is a good possiblity.
I honestly haven read his book or the refutations of it, but its not a strecth, and and Zheng He's logs of his last two voayages were destroyed by
the succesive emporer. But they did make it as far as africa.
Imagine how different the world would be if some of the early attmepts exploration were more succesful
[edit on 20-7-2009 by punkinworks]