The Roman Empire was one of the largest and most powerful empires in world history, spanning over 2 million square miles and containing over 60 million citizens at its peak. The Romans built an extensive network of over 50,000 miles of roads connecting their widespread empire and engineered advanced aqueduct systems and public baths using running water well before modern times. According to legend, Rome was founded in 753 BC by the brothers Romulus and Remus, descendants of the Trojan hero Aeneas.