Ancient Levadia was associated with the Oracle of Trophonius, the chthonian local deity that operated probably from the 6th century BC in the wider area of Kria. The fame of the Oracle with the awe and mysticism it exuded, gradually established Levadeia as a renowned religious centre and holy city of the Boeotians. At the springs of Kria, Lithi and Mnimosini, in what is considered the area of the Oracle, the Sacred Grove is developed.

The religious needs of the operation of the Oracle and the development of the worship of Zeus Vasileos from the 4th century BC, gradually transformed the city into an artistic center until the late Roman period. Workshops were developed for the production of tombstone monuments, ceramics, idols, votive offerings, jewellery and objects of everyday use, characterized by excellent quality and rich imagination in the composition of the figurative types.

The 2nd century AD traveler Pausanias describes the place and the function of the Oracle, the mystical process, the way of oratory, the preparation, reintegration and care of the worshipers and mentions that thanks to the Oracle, Levadeia was considered a holy city. He also mentions Levadia as a city highly decorated like many rich Greek cities, with many magnificent temples and sanctuaries and a lot of great statues adorning the famous Sacred Grove that surrounded the Trophonic Oracle. Other ancient writers also refer to it. A statue sculpted by Praxitelis (famous ancient sculptor) in honor of the hero-god is mentioned in the area of the Oracle of Trophonius, among others dedicated to Saturn, Zeus, Hera and Demeter Europa.

Scattered carved votive and worship niches are preserved in the steep rocks of the area.