What made communication between the cities of Greece difficult?

Communication between the cities of ancient Greece was difficult due to the region's mountainous terrain, which created natural barriers and isolated city-states from one another. Additionally, the lack of a unified language or standard system of governance further complicated interactions. Travel was slow and dangerous, relying on foot or primitive boats, which limited the frequency and efficiency of communication. These factors contributed to the development of distinct cultural identities and rivalries among the city-states.