How did the aztecs apply their engineering skills to the challenges of living on an island?

The Aztecs had remarkably impressive engineering skills, which helped them solve many of the difficulties of being located in an island.

One of the greatest examples of this, is the canal they built from the capital of Tenochtitlan, to Chapultepec, which helped them transport fresh water from the shores into the city. It was absolutely essential to their sustainability, as even though they had enough water for agriculture, it was salty water that couldn't be drank.

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