The temple of Apollo Daphniforos is the most important and wider known monument of Eretria. Together with its enclosure it constituted the sacred temenos of Apollo, a religious centre and fundamental place of worship within the core of the ancient city, to the north of the Agora. According to the Homeric hymn to Apollo, when the god was seeking for a location to found its oracle, he arrived to the Lelantine plain. The first temple is dated to the Geometric period and was situated probably near the harbour, as the sea then reached the area of the Agora. The hecatompedon (hundred-footer) apsidal edifice is the earliest in its type among those mentioned by Homer, and slightly posterior to the hecatompedon temple of Hera on the island of Samos. It was flanked to the south by another apsidal building which also came to light: the so called ?Daphniforio? or ?space with laurels? (7.5 x 11.5m) is the most ancient edifice in Eretria, related to the early cult of Apollo in Delphi. At the centre of this edifice were preserved the clay bases supporting the laurel trunks that propped up the roof. In the early sixteenth century a second hecatompedon temple was erected through earth fills upon its Geometric predecessor, on a solid artificial terrace. This temple disposed of wooden columns (six at the narrow sides and nineteen at the longer sides), and was subsequently covered with earth in order to build the later and most renowned of all temples in the city.

Construction started at the late sixth century BC (520-490 BC) and the temple was perhaps still unfinished when the Persians razed the city in 490 BC. Poros stones and marble were the materials used for this Doric peristyle (surrounded by colonnades) temple (6 x 14 columns). It had a prodomos (anteroom) and an opisthodomos (back section) arranged with two columns in antis; the cella (in Greek sek?s) was divided into three naves by two interior colonnades. After the destruction of the city by the Persians, the temple was repaired and remained in use; yet in 198 BC it was destroyed again, this time by the Romans, a fact which initiated the gradual abandonment and dilapidation of the monument until the first century BC. Unfortunately, the majority of architectural parts from this temple and other sanctuaries of the city were re-used as construction material; only a few (column) drums together with fragmented capitals and triglyphs remain from the superstructure of the monument. Of the sumptuous sculptural decoration survive only parts of the west pediment featuring in relief the fight of the Amazons (or Amazonomachy, a usual motif for the iconography at the time). The centre was occupied by Athena and is partially preserved, depicting her trunk with the Gorgoneion on the thorax; a superb work of art is the complex of Theseus and Antiope marked by sensitivity and softness of the form, internal force and clarity, despite the ornamental tendency obvious in the coiffures and the folds of their clothes. These sculptures are impregnated by the rules of archaic plasticity; the analogies are rendered in an innovative manner, a precursor to the idealization and the force of the classical art. The entire composition supposedly featured chariots to Athena's right and left, one chariot presumably carrying Theseus and Antiope, while Hercules might ride the other, and the picture could be complemented by fighting Amazons and a dead warrior. The east pediment possibly narrated the Gigantomachy (fight of the Giants). The details of the faces and the clothes were coloured, thus rendering the depiction more vivid. Fragmented sculptures that may be part of the temple after the destruction by the Persians (warrior, Amazon and Athena's trunk) have been located in Rome. Today are visible only the foundations of the Post-Archaic temple, as well as remains of the Geometric temples uncovered in lower deposits.

The temples in the temenos of Apollo Daphniforos were excavated between 1899 and 1910 by Κ. Kourouniotis. Further investigations were conducted by Mrs. I. Konstantinou and by the Swiss Archaeological School.