A polis, though divided by physical features, was much more than a mere region - it was a community of people. To the Greeks, the polis clearly meant more than the modern description of a city-state. Qualities like a sense of security and peace, liberty of social interaction and thoughts, self-sufficiency, and a feeling of togetherness made the polis a prized possession. It was a way of life for the Greeks in the political, moral, cultural, and economic sense. The Greeks were a piece of the polis, and the polis was a piece of them.
One of the most significant reasons that the polis was held in such high regard by the Greeks was because it was such a secure and peaceful place. Although many poleis existed throughout the land of Greece, the physical attributes of the land such as mountains, averted any attempts of fighting or assault from another polis. This allowed the people of the polis to feel a sense of safety and peace knowing that no harm or conflict would come upon them. The Greeks had no reason to invade other poleis because they stayed within the polis which made life in a polis much easier and out of harm's way.
In addition, the polis allowed speech and thoughts to be shared freely. People of a polis socialized daily about things such as politics, the arts, and news around the polis. This was generally done in the Agora which was absolutely essential part of any ancient Greek city. It was a place where political activity and governance of the Greek city-states occurred. Also, it was the center of commerce and trade for the city-states. It was typically located in the center of each city. This was a daily part of the Greek's life and this was a place treasured by the Greek and played a large role in the communal feeling of the polis. .
Because of the above conditions and more, the polis was extremely self sufficient. It relied wholly on the people of the polis to produce enough for everyone.