Archaeologists dig up 1,400-year-old Native American canal in Alabama
It's interesting that while South-American pre-colombian construction projects are familiar to many (such as Aztec cities and Nazca Lines, etc), it is perhaps not as well known that North-American pre-columbian populations had massive civil engineering projects as well e.g. https://en.wikipedia.org/wiki/Poverty_PointI wonder why the latter are not as well known.