This paper presents a review of the history of the insular telephone network of Tenerife (RTIT). The development of this telephone service was the best example in the Canary Islands of the commitment of a local administration, as its implementation represented a great economic effort at a time when the economy of the archipelago had not yet recovered from the crisis of the Great War. With this, it was possible to create a communication ring that managed to connect almost all the inhabited nuclei on the island, which continued even beyond the concession of the telephone monopoly in Spain to the CTNE in 1924.