These lines were built as detailed below:[3] The company always faced tough competition from the various large British-owned railway companies operating in the Province who had already built lines in those areas where most profit was to be made.

When the Government of Juan Domingo Perón took over the railways in 1948, the CGBA became part of Ferrocarril Belgrano.

In 1961 the Government of Arturo Illia decided to close all the lines that were uneconomic so many branches were closed, such as the CGBA's G3 (to Port of La Plata), G4 (to General Villegas), G5 (to Victorino de la Plaza) and G6 (to Vedia).

Although some branches would be re-opened later, those reopenings were temporal, being the most of them definitely closed in 1977 by the de facto government in power in Argentina by then.

As a result, the Buenos Aires-González Catán branch was operated by the consortium UGOFE until February 2014 when the whole Belgrano Sur Line was re-privatised and given in concession to private company "Argentren" of Emepa Group.