The formal purchase of all Macedonia's rail networks by the Greek state proved more difficult than the liberation of its soil. It was not completed until 1928 after interminable negotiations with the European companies involved. Nevertheless, their unification with the lines in southern Greece was officially accomplished much earlier, in May 1916. At that time, King Constantine I, in a symbolic ceremony near Kolindros, placed the last nail, making the link with Europe a reality -- a Greek dream 30 years overdue.
In subsequent years, military and economic needs dictated the laying and dismantling of several kilometres of track. During the First World War, in 1916, in order to meet the requirements of the Macedonian Front, a French concern constructed a narrow line (decoville) from Skydra to Aridaia; this line, being of no interest financially in peacetime, ceased to operate in 1936. Its slow-moving engines were transferred to the Sarakli-Stavros line, of the same width and age, where they continued to run until 1947.
Also ill-fated was the similar Myrini-Amfipoli port line. This project, which was officially completed in May 1940, was put out of operation only a few months later with the declaration of war between Greece and Italy.
In 1943, during the Bulgarian occupation of eastern Macedonia, the Sidirokastro-Promahonas-Koulas line was constructed, only to be dismantled in 1951 and rebuilt in 1964-65 -- a faithful reflection of the fluctuations in Greek-Bulgarian relations.
In January 1955 the trains in western Macedonia, which since 1952 had run as far as Ptolemaida, via Amyntaio, were extended up to Kozani. The era of ambitious railway projects came to an end in the 1960s, giving way to the age of the automobile which was already in full swing.