« Paris is built over a system of caverns from which the din of Metro and railroad mounts to the surface, and in which every passing omnibus or truck sets up a prolonged echo. And this great technological system of tunnels and thoroughfares interconnects with the ancient vaults, the limestone quarries, the grottoes and catacombs which, since the early Middle Ages, have time and again been reentered and traversed. Even today, for the price of two francs, one can buy a ticket of admission to this most nocturnal Paris, so much less expensive and less hazardous than the Paris of the upper world. The Middle Ages saw it differently. Sources tell us that there were clever persons who now and again, after exacting a considerable sum and a vow of silence, undertook to guide their fellow citizens underground and show them the Devil in his infernal majesty. A financial venture far less risky for the swindled than for the swindlers: Must not the church have considered a spurious manifestation of the Devil as tantamount to blasphemy? In other ways, too, this subterranean city had its uses, for those who knew their way around it. Its streets cut through the great customs barrier with which the Farnlers General had secured their right to receive duties on imports, and in the sixteenth and eighteenth centuries smuggling operations went on for the most part below ground. We know also that in times of public commotion mysterious rumors traveled very quickly via the catacombs, to say nothing of the prophetic spirits and fortunetellers duly qualified to pronounce upon them. On the day after Louis XVI fled Paris, the revolutionary government issued bills ordering a thorough search of these passages. And a few years later a rumor suddenly spread through the population that certain areas of town were about to cave in. » [C2,1]
Ancient Paris, Catacombs, Demolitions, Decline of Paris, in The Arcades Project, Walter Benjamin, p. 85
Ce texte souligne l'existence de nombreux passages creusés sous Paris, tandis que ce projet propose un site permettant d'accéder à un sous-sol depuis Lausanne. Or, lors du projet MEASURES, la relation entre les deux villes s'était faite par la cave. De plus, le DOUBLE-ELEMENT avait déjà été conçu comme un espace permettant d'accéder à une ville depuis l'autre.
C'est pourquoi il a été décidé qu'une porte serait introduite au bout du chemin proposé par ce projet: en arrivant devant la façade de Lausanne, le sujet suppose un sous-sol. D'abord forcé par la structure du bâtiment à monter des marches pour entrer dans la maison, il est ensuite guider à la cave par la colonne + . Au fond il y découvre une porte, qui mène sur Paris.