I know this is...

Many discussions place the year 3500 BC as the approximate time the wheel was invented. The place is Mesopotamia, the area now occupied by Iraq. The first wheel for transportation purposes is approximated to 3200 BC, its purpose being to move the Mesopotamian chariots.

Although there are signs that the very beginning of the wheel goes back to the Paleolithic era (15,000 to 750,000 years ago). I think that makes it heritage.

So what's missing from my list of things that make up our heritage? It wouldn't make sense without it, but it's often the last on the list...