Archaeological investigation in Delphi started in the second half of the 19th century, but it was not until 1892 when a systematic excavation began under the direction of Théophile Homolle and the French Archaeological School of Athens. The "Great Excavation" (La Grande Fouille) lasted 10 years and was concluded by the creation of the first museum on-site. In the years to follow, the site never ceased to be excavated and investigated. Several of the monuments were restored and new interpretations continue to see the light in the academic field.
In the course of the Ottoman period the archaeological site of Delphi was often visited by European travelers, inspired by the Renaissance spirit. The first one was Cyriacus of Ancona in 1436. The backwater village of Kastri in Phocis became renowned through their descriptions, sketches and engravings. Yet, although the site of ancient Delphi had been securely identified, it was very difficult to start a systematic excavation, as the expropriation of an entire village was almost impossible given the meager finances of the newly founded Greek State. Some trial sections had taken place in 1840 and 1860 around the polygonal wall. An earthquake in 1870, however, created new hopes. The village was left derelict after it and in 1880 B. Haussoulier managed to start excavating the Portico of the Athenians.
Under Charilaos Trikoupis the Greek state got on the track of modernization and long-term planning. A close collaboration between France and Greece was achieved, part of which was on the field of cultural heritage and archaeology. Thus, in 1892, under the auspices of the French Archaeological School, started the “Great excavation” (La Grande Fouille). Great, not only in length of time, but also in what regarded the extent, the difficulty, the number of people who were mobilized and, of course, the number and importance of the monuments and finds discovered. The diary of this amazing effort has been digitized by the French Archaeological School at Athens offering a glimpse at the fascinating and copious efforts of the archaeological team, which comprised members of various nationalities. The entire village of Kastri was transferred to the location where now lies the village of Delphi. The technical teams provided the site with a mini-railway with wagonets, in order to remove the debris, and started demolishing the old houses. After all the preparatory work, the actual excavation started in mid-October 1892, quite late in autumn, and therefore it did not last for long. The next season, however, started in April 1893, revealing large part of the Treasury of the Athenians as well as Sibyl's Rock and the Altar of the Chians. Within the next years came to light most of the buildings along the Sacred Way as well as unique sculptures. One of the most exciting moments was the discovery of the Charioteer, part of the monumental bronze sculpture dedicated by the tyrant of Gela, Polyzalos, in order to commemorate his victory at the Pythian Games. Other highlights of the excavations were the discovery of the Dancers of Delphi as well as of the Roman statue of Antinous and of the pair of archaic kouroi (Dioskouroi or Kleobis and Biton). After revealing the monuments within the sanctuary of Apollo the archaeologists started excavating the stadium and the gymnasium and then moved on to the so-called “Marmaria”, i.e. the sanctuary of Athena Pronaia, from where the locals used to pick building material for centuries. The team of the archaeologists comprised several big names of French scholarship, such as the director Th. Homolle, the architect A. Tournaire, Henri Corvet, P. Perdrizet, and academics such as Th. Reinach and H. Weil, who undertook the study and enhancement of the epigraphic material. However, it was not a solely French, but rather an international team, as it comprised also scholars of other nationalities, notably Greek and German.