The municipality of San Giovanni Suergiu had its greatest development due to the fact that it became a very important railway junction. The great development of the mining industry led to the establishment of the Sarde Meridional Railways Company, which built two narrow-gauge railway lines of great importance for the Sulcis Iglesiente-Basso Sulcis connection. The two lines were both inaugurated on May 23, 1926 and were: the Siliqua-Palmas Suergiu-Calasetta and the Iglesias-Palmas-Suergiu (with the present San Giovanni Suergiu).
Maximum traffic development occurred in the 1940s-50s coinciding with the period of highest coal production in Sulcis.
