Aristophanes (Aris) Tsalikis held the position of R.H. Keays’s first assistant. Tsalikis is the typical example of an engineer, who after completing his studies in Munich, gained valuable experience abroad, working on the large-scale railway and plumbing projects. He worked on the Marathon project from 1925 to 1929. After that, he was appointed general director of the Technical Works Department of the Ministry of Rural Development and Food. Tsalikis was the one who shared his knowledge concerning the construction site with his fellow Greek engineers. The difficulty in communicating with the Americans guided to the selection of engineers who were fluent in foreign languages, such as the Constantinopolitan Theologos Genidounias (1871-1938), a Cypriot who grew up in Smyrna Nestor Nestoridis (1888-1955), the Corfiot Petros Loprestis (1870-1941) and Dimitris Diamantidis (1871- 1926).