Claros is an ancient Ionian site located in Ahmetbeyli village near Ozdere, about 50 kilometers south of Izmir. Other ancient sites nearby are Kolophon which is about 13 kilometers nortwest of Claros; Notion which is 3 km south; and Ephesus 18 kilometers east of the site. Some historians beleive that the name of the site comes from the Hellenic language which meant "land" or "future guessing", but others say that it comes from the Luwi language, a local Anatolian language, and means "shore" or "pier". In fact, Claros was built by the sea as an "oracle center" of the city of Kolophon, one of the 12 Ionian cities in the Aegean. Besides the cult of Apollo Klarios, there was a huge temple used for reading god Apollo's oracles during the Hellenistic period, same as in Delphi and Didyma. According to Homeros, the Apollonian cult of Claros dates back to around 7th or 6th century BC. The temple was plundered by pirates and the site was destroyed around 3rd century. Many of the inhabitants of Kolophon left the area during the Roman period therefore Claros lost its importance as its cult, and was silted by the river.

The site of Claros was first discovered in 1905. The columns of the propylon (monumental gates) at the beginning of the sacred road were found buried in a field, the site was completely under the soil caused by the silting from the Ales (todays Avci) river. The propylon is from 2nd century BC with a doric style placed on a square grid and there are three rows of steps giving access to the entrance. Its walls are decorated with inscriptions. The propylon was an entrance for those who came by the Aegean Sea and connected the pier to the temple with a sacred road. On both sides of this road there were statues of important people from the period and their inscriptions.

The temple of Apollo was built in the 3rd century BC, with some elements completed around 2nd century AD during the Roman period. It's also supposed that there should be a smaller scale temple before this one, probabily from the Arcaic period. A monumental altar is sitting right in front of the temple. The dimensions of the temple of Apollo are 26 meters by 46 meters and it has a doric style in peripteros plan, with 6 x 11 columns rasing on 5 rows of steps. There was a 7,5 meters tall statue of Apollo in the cella (cult room), along with the statues of his sister Artemis and their mother Leto. The "oracle reading room", known as "adyton", was located below the cella. According to ancient sources, unlike in Delphi where female priests (Pythia) used the deliver the oracle of Apollo to the visitors, here at Claros men priests did the job. In this dark room the priest drank the sacred water from the square-shaped well and then referred the oracle of Apollo to the people in a poetic way.

Today the site is in good shape and open to the visitors. Several artifacts were found during the excavations, such as small statues and objects made of bone, ivory, bronze and silver. These artifacts are on display at the archaeological museum of Ephesus, in Selcuk town.