The Temple of Apollo is the most important and most famous monument of Eretria. Along with the precinct was the sanctuary of Apollo, the religious center and the main place of worship of the ancient city, located in the central core, north market. According to the Homeric Hymn to Apollo, when God was looking place to set up his oracle, and arrived at Lilantio field. The first church dates to the Geometric period and probably was located near the port and the sea, then reached up to the market area. It Hekatompedon vaulted building, the oldest of this kind from those mentioned by Homer and a little later by Hekatompedon temple of Heraion of Samos. Beside him, in the south, it revealed another vaulted building, the oldest in Eretria, called Dafniforio (7,5 x 11,5 m.), Associated with the early cult of Apollo at Delphi. clay bases underlying the laurel logs fastened to the roof in the center of the building remained. In the early 6th century. B.C. He built on the geometric, a second Hecatompedon temple after filling and a strong embankments. This church had wooden columns, 6 on the narrow and 19 on the long sides, and he epichothike to build the new, the most distinguished of all city churches.
Its construction began in the late 6th century. B.C. (520-490 BC) and probably had not yet been completed, when the city was destroyed by the Persians in 490 BC He was Doric peripteral with 6 x 14 columns, built of limestone and marble. Did vestibule and opisthodomos with two columns in antis and the nave was divided into three naves with two colonnades inside. After the destruction of the city by the Persians, the church was repaired and continued to function, however, it was destroyed again in 198 BC by the Romans, which marked the gradual abandonment and ruination until the 1st century. B.C. Unfortunately, most of the architectural elements of the temple and other temples of the city were reused as building material and the superstructure of the monument have only survived some vertebrae, capitals and triglyphs fragments. From the magnificent sculptural decoration are preserved parts of the relief representation that adorned the west pediment, which depicted the Amazons, common representation in the iconography of the era. Central location was Athena, from which the body is preserved with gorgoneion chest and exquisite art is the complex of Theseus by Antiope, characterized by tenderness and softness in volumes, inner strength and clarity, despite the decorative trend in headdress forms and aspects of their clothing. In these sculptures are now well established rules of archaic sculpture and performance forms possesses a new life, which will lead to idealism and power of classical art. The overall performance can be filled with floats right and left of Athena, one of which will be aboard Theseus by Antiope, and the other perhaps aboard the Hercules, and the scene should be closed with militant Amazons and dead warrior. The east pediment depicted perhaps the Giants. The details of the faces and forms of clothing rendered with color, giving vitality to the show. In Rome they identified sculptures parts, believed to belong rather to the construction of the temple after the Persian destruction (warrior, Amazon and Athena trunk). At the site today are visible only the foundations of the Late Archaic temple and the remains of geometric temples uncovered in the lower layers.
The temples of Apollo excavated between 1899-1910 by K. Kourouniotis. Investigations were also made by I. Constantine and the Swiss School of Archaeology.