According to ancient legend, the city of Rome was founded on April 21, 753 BC. The story says twin brothers named Romulus and Remus were raised by a wolf. When they grew up, they wanted to build a city. They argued over where to put it. Romulus chose a hill called Palatine Hill. He began building walls there. The new city was named Rome after him. Nobody knows if this story is true. But we do know Rome became a powerful civilization. The Romans built roads that stretched across Europe. They created an aqueduct system that carried clean water to cities. Roman architects designed buildings with arches and domes. Some of those buildings still stand today. The Romans also created a system of laws. Many modern countries base their own legal systems on Roman ideas. Rome's influence lasted long after the empire ended. Today, people still celebrate the founding of Rome on April 21.