How did Greece's geography influence the city-states?

Athens,
Thebes, Sparta, and Corinth are some of the most well-known city-states of ancient Greece.
Instead of having a centralized administration, Greece developed several powerful city-states
between 800 BC and 400 BC. Greece has a mountainous terrain made up of isolated archipelagos.
These islands enabled Greece to form numerous powerful city-states instead of just one. It was a
defense move meant to protect the Greeks from external attacks. Most city-states had a thriving
agricultural sector due to the hilly and fertile terrain of Greece. There was also plenty of
water from natural springs. Another reason why city-states developed is because of the rocky
terrain that didn't allow people to travel much. Overall, the history of Greece has been shaped
by its terrain. Those islands led to the formation of city-states that gave Greece worldwide
recognition.

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