Editing Pre-Columbian era (section)

=== Upano Valley cultures ===
{{Main|Upano Valley sites}}
In the [[Upano River]] valley of eastern [[Ecuador]], several cities were established by the Upano and Kilamope cultures around 500 BCE.<ref name="Sci.org">{{Cite journal |last=Wade |first=Lizzie |date=11 January 2024 |title=Laser mapping reveals oldest Amazonian cities, built 2500 years ago |url=https://www.science.org/content/article/laser-mapping-reveals-oldest-amazonian-cities-built-2500-years-ago |url-status=live |journal=[[Science (journal)|Science]] |doi=10.1126/science.zzti03q |archive-url=https://web.archive.org/web/20240112000516/https://www.science.org/content/article/laser-mapping-reveals-oldest-amazonian-cities-built-2500-years-ago |archive-date=12 January 2024 |access-date=12 January 2024}}</ref><ref name="BBC">{{Cite web |last=Rannard |first=Georgina |date=11 January 2024 |title=Huge ancient lost city found in the Amazon |url=https://www.bbc.com/news/science-environment-67940671 |url-status=live |archive-url=https://web.archive.org/web/20240111234436/https://www.bbc.com/news/science-environment-67940671 |archive-date=11 January 2024 |access-date=12 January 2024 |website=[[BBC News]]}}</ref> The cities in the Upano Valley consisted of agricultural societies that cultivated crops such as [[corn]], [[manioc]] and [[sweet potato]]. The cities fell into decline around 600 CE.<ref name="Guardian2">{{Cite web |date=11 January 2024 |title=Valley of lost cities that flourished 2,000 years ago found in Amazon |url=https://www.theguardian.com/science/2024/jan/11/amazon-archaeology-lost-cities-ecuador |url-status=live |archive-url=https://web.archive.org/web/20240112002219/https://www.theguardian.com/science/2024/jan/11/amazon-archaeology-lost-cities-ecuador |archive-date=12 January 2024 |access-date=12 January 2024 |work=[[The Guardian]]}}</ref>