What features did the ancient Greek and Roman civilizations have in common?

Both ancient Greece and Rome had the same gods and goddesses, only with different names. Example, the ancient Greek god of the seas was Poseidon, while in ancient Rome, his name was Neptune. Also, ancient Greeks and Romans lived near water for food and water resources and trading routes. Lastly, ancient Greeks and Romans had very powerful armies, which helped them conquer many other civilizations.