Classical Athens was a powerful city-state. It was a centre for the arts, learning and philosophy, and the home of Plato's Academy and Aristotle's Lyceum. It is widely referred to as the cradle of Western civilization and the birthplace of democracy, largely because of its cultural and political impact on the European continent—particularly Ancient Rome. In modern times, Athens is a large cosmopolitan metropolis and central to economic, financial, industrial, maritime, political and cultural life in Greece. In 2021, Athens' urban area hosted more than three and a half million people, which is around 35% of the entire population of Greece.