Didyma is the main temple of Miletus  and it was dedicated to Apollo. It was believed even in ancient time that the temple existed before the Ionian settlers. The Persians destroyed the Ionian temple during the Ionian revolt and today temple that we see is from Hellenistic period.

Temple never exactly finished. However, in antiquity it was important oracle centre. It lost its importance in Christian period and a church was built inside the temple.
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