The colonization of Beringia appears closely linked to the arrival of the oldest firmly documented archeological tradition in mid-latitude North America (Paleoindian). The discovery of a Paleoindian complex in central Alaska, combined with the recent redating of the Bering Land Bridge and key archeological sites, suggests that Beringia was settled during the final Pleistocene interstadial (12,000 to 11,000 years before present). Its population expanded rapidly into other parts of the New World. Beringia probably was colonized in response to changes in climate and vegetation that occurred during this interstadial. Access to the Americas was controlled by Beringian environments and not by changing sea levels or continental ice masses.