The text analyzes the process of construction and operation of the Ferrocarril de Bolivar, which despite its limited extension, generated significant economic activity and a profound change in the dynamics of power in the Bolivar Grande (which included several of today's Colombian departments), as it allowed the thriving development of one of its subregions in the second half of the nineteenth century. The study of the construction contracts for this railroad provides a clear view of the Colombian states vulnerability with respect to greedy investors, who saw in railroads an opportunity for financial speculation.