Athens was known for its beauty in architecture, even after their defeat in the Peloponnesian war, Spartans refused to destroy the town, the same happened with any war later on. In one myth, the gods admitted the towns beauty and decided to give it an immortal name, so they held a contest of sorts to see who the town admired most, the goddess, Athena, won. So the town would now refer to itself as "Athens".
Athens was also a "Representative Democracy", a government of which the citizens where represented by a person or group of people. In this case, the citizens where represented by "The Council of 500". Every year or so, someone would draw names to be in the new Council.
Athens was near an ocean, and was not anywhere near a river. Because the ocean water consists of salt, it is not very drinkable. Therefore they where forced to trade for clean water, and instead of working for the things they needed, they simply traded. So because of this, the entire economy relied on trade, leaving time for things like architecture and learning more about the world. So not only where they great architectures, they where also very intelligent for their time.