Ancient Corinth located 7km south of the modern city of
Corinth (the new city was built after the big earthquake of 1858). Although the modern Corinth has nothing to offer to a tourist, the Ancient Corinth is an interesting and easy day trip from Athens which is 85km away(the organized tour come in the morning and return in Athens in noon).
By the way, it seems that the area was inhabited since 4000 BC (probably the huge amounts of waters is the main reason). Aeolic tribes were there before 1000BC but it was the Dorians at about 900BC that came here after taking Megaris from Athens. One century after Korinthian people established colonies at Syracusses and Corfu and that brought a lot of money to the economy of Corinth so the city of Corinth became as big at the other big powers of that era. After fighting against the Persian army they fought against Athens that had a new big navy power. During the peloponese war Corinth fought together with Sparta and Athens lost but during the Corinthian war they joined forces with Athens!
The city of Corinth destroyed by Romans in 146BC although it was rebuilt in 44BC by Julius Ceasar.
During the ottoman occupation the Acrocorinth changed hands many times and after the greek revolution Corinth some had the idea to be the capital of Greece but of course the big earthquake a few years later (1858) put the plan in history. The new city of Corinth was built 7km away but it was destroyed also by another earthquake in 1928!