Which invention & discoveries help to invent horse cart?

or:Which invention & discoveries help to invent horse cart?or:First you have to have horses, and then you have to have flat ground. The Aztecs never

or:Which invention & discoveries help to invent horse cart?

or:First you have to have horses, and then you have to have flat ground. The Aztecs never invented a wheel because they lived in mountains and a wheel is not very useful. Other cultures invented the wheel very early in history. Interestingly, it seems that the potter's wheel was invented a long time before the rolling wheel. No idea why.

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