The middle east used to be an important route for? ?

For trade

Explanation:

These trade routes were a connection between East and West. Trade routes may be established by land or by water. In the case of the Middle East, one of the most traditional trade routes was the spices and the silk route. Silk and spice routes interconnected various empires across Europe and Asia, including the Roman Empire and the Han Dynasty, around the 1st century. These routes connected a number of trading points and crisscrossed much of the hitherto known world. Trade routes made by land were called the "Silk Road" and by sea were known as the "Spice Road".

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