On my personal website, the error page displayed when a resource is unavailable (the famous 404 error) is a reproduction of a page (page number 404) from an issue of the journal La Revue des deux mondes (en: Journal of the Two Worlds). The beginning of the text reminds us error messages terminology, because it mentions “problems” related to the sewerage beneath the city of Paris. The online reader is thus invited to draw an analogy between these “two worlds”: on the one hand, urban infrastructure (described in the text in very concrete terms) and web infrastructure (which is by no means “dematerialized”).

The title of the work, The Lonely Mountain, is a paraphrase of the concept of an isolated vertex from graph theory (used in the study of networks), i.e. a point in a graph that is not connected to any other. In the fictional universe of J. R. R. Tolkien, this name refers to a mountain beneath which lies an underground city.