As early as 1921, the British writer D. H. Lawrence, in his book, Sea and Sardinia, recounted his experiences while traveling along the Cagliari–Isili line: We'll take the secondary train, … wherever it goes.After World War II, railway tourism slowly took shape on the island.

By the 1980s, the then concessionaires of the secondary lines, the Ferrovie Complementari della Sardegna [it] (FCS) and the Strade Ferrate Sarde [it] (SFS), were forced to organise a service for tourists in a more systematic fashion.

The name chosen for it, Trenino Verde, was used for the first time in 1984,[1] and alludes to the many features rich in vegetation encountered by the trains.

Given the growing demand for rail tourism, the Ferrovie della Sardegna (FdS) (created in 1989 from the merger of the FCS and the SFS), with the support of Ente Sardo Industrie Turistiche [it] (ESIT), the World Wide Fund for Nature, and Italia Nostra, later obtained funding from the Region and the European Union to achieve a leap in the quality of the service.

The funding was spent on the restoration of steam locomotives, vintage carriages, stations and sections of line.