Excavations in the archaeological site of Phthiotic Thebes started in 1924 from G. Soteriou and continued in 1956 from P. Lazarides on the expenses of the Archaeological Society, which still finances the excavations after the death of the academician P. Lazarides.

The excavations have yieleded a large number of important monuments dating from Late Roman to Early Christian times down to the 7th century, when the city was destroyed. The most impressive of the finds are the mosaic floors, with their wide repertoire of motifs and flawless technique.

The most important monuments are:

- Basilica A' of St. Demetrios. An early christian church in the type of basilica with nave and two aisles. We can distinguish different chronological phases from 4th to 6th century. This archaeological site includes two bath-houses and an ancient avenue with shops.

- The basilica of Bishop Peter. With different chronological phases from 4th to 6th century. Martyrium Basilica from 4th to 6th century.

- Basilica of Cemetery.

- Bishopric Mansion.

- Non religious building.

- Basilica B'of Bishop Elpidios.