Tango music is the protagonist of this journey that is unfolded along an area with a unique profile. The former collective houses (conventillos) and the traces of the European immigration of San Telmo, the brothels area of La Boca, and Barracas’ factories ambience are the attractive sites of a journey that reviews the origins of tango.  We here underline its development from dance to tango-song, from the performing with flute to bandoneón, from the old guard (guardia vieja) to its golden age, from the improvised marginal music to the compositions by Astor Piazzola. Fundamental pieces of this gender are listened to along the ride while a nurturing analysis of its evolution is provided. Furthermore, tango lyrics are read for an in-depth appreciation of its peculiar poetics while sharing some anecdotes and biographies of its most important representatives.