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Each Monday, this column turns a page in history to explore the discoveries, events and people that continue to affect the history being made today.
You've got the gold I need for my necklace and I've got the silk you need for your robe.
What to do?
Nowadays, if you need something, you go to the closest mall, shell out a few bucks and head home. Thousands of years ago, the process wasn't nearly as simple. If you or someone in your town didn't grow it, herd it or make it, you needed to abandon that desire or else travel for it, sometimes over great distances. For many towns, the effort of trade was too much. Those ancient towns make only rare appearances in our history books
