Why did a system of roads the romans develop economically and politically?

Roadways were the lifeblood of Ancient Rome. Over the course of 700 years, the Roman built more than 55,000 miles of paved highways throughout Europe - enough to encircle the globe. These engineering marvels ensured the swift movement of goods, soldiers and information across the empire and played a crucial role in tightening Rome's grasp on the Mediterranean Basin both economically and politically. The Romans earned a lot of revenue through trade made possible by ease of transport on their roads. They would charge a tax for use of the roads.

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