The dam is often cited for its role in the modernization of Greece and the first recorded case of seismic activity associated with reservoir inundation.

The Marathon Dam was originally proposed, designed, funded and tendered in 1918, but was declared illegal by Prime Minister Dimitrios Gounaris, who succeeded Eleftherios Venizelos in late 1920, because there had been no public bidding for the project.

With a strong influx of Greek refugees from Asia Minor following the defeat at the Greco-Turkish War of 1919–1922 (the "Asia Minor Disaster") and the 1923 Treaty of Lausanne, which led to the population exchange between Greece and Turkey, Greek officials were searching for a means to supply Athens with more water.

At the time, Greece underwent a period of political turmoil that saw the fall of the monarchy and the establishment of a Second Hellenic Republic, as well as several military coups and counter-coups.

Near the end of this period, all major water supply projects for Athens were reevaluated and a five-volume report was published.

[2] The foundation stone for the dam was laid in October 1926 by Prime Minister Alexandros Zaimis; Venizelos was also present at the ceremony.

A plaque on the temple reads:[1] "To commemorate their victory at the battle of Marathon, the Athenians erected a treasury at Delphi.

This building is a replica and commemorates a victory at Marathon in wrestling from nature its life giving water for the citizens of Athens.