The residualised street can, in turn, all too easily become ‘no more than a traffic sewer or refuge collection zone’ (Trevor Boddy) –a place inhabited by the marginalised groups excluded by the security guards and cameras that police the corporate, interior zone. (…) the air-conditioned interior skywalk cities will also exaggerate the urban heat-island problems.

Stephen Graham, Vertical.

Die Mehrzahl der pariser Passagen entsteht in den anderthalb Jahrzehnten nach 1822. Die erste Bedingung ihres Aufkommens ist die Hochkonjunktur des Textilhandels. Die magasins de nouveautés, die ersten Etablissements, die größere Warenlager im Hause unterhalten, beginnen sich zu zeigen. Sie sind die Vorläufer der Warenhäuser. Es war die Zeit, von der Balzac schrieb (…).

Walter Benjamin, Gesammelte Schriften, Band V.1, Das Passagen-Werk.

The inhabitants would blow up the catwalks: This is a picture of anti-reason itself, of error, of thoughtlessness. Madness. And all the solutions come to the same thing: separation of traffic according to speed. The pedestrian, from now on, will be confined to raised walks build up above the street, while traffic lanes remain at their present ground level. Madness.

Le Corbusier, Ville Radieuse, 1928.

Wider processes of social polarisation have often worked to exaggerate the social separation of inside and outside within the downtowns of various North American cities. […] the city’s skyway system ‘became something it was never intended to be: a fortress, a filter, a refuge.’ The city’s downtown street system –an increasingly residualised space for the poor, the mentally ill and the failed consumers externalised from the interior system– became a source of fear for those inside.

Stephen Graham, Vertical.

Among the innovations which have transformed North American cities in the past 40 years, the development of discrete, grade-separated pedestrian networks in the downtown core areas is surely one of the most remarkable … The idea of an interior city from which one might never need to step outdoors, is on the point of realisation in a score of locations across the continent.

Barry Maitland, ‘Hidden Cities: The Irresistible Rise of the North American Interior City’ in: Cities 9:3, 1992.

Les architectes s’acquittèrent on ne peut mieux de a mission qui leur était confiée. Au premier étage de chaque maison, ils prirent toutes les pièces donnant sur la rue et en démolirent les cloisons intermédiaires, puis ils ouvrirent de larges baies dans les murs mitoyens et ils obtinrent ainsi des rues-galeries qui avaient la largeur et la hauteur d’une chambre ordinaire et occupaient toute la longueur d’un pâté de constructions. Dans les quartiers neufs où les maisons contiguës ont leurs étages à peu près à la même hauteur, le plancher des galeries se trouva être assez régulièrement de niveau … Mais dans les vieilles rues (…) – Tony Moilin: Paris en l’an 2000, Paris, 1869.

Walter Benjamin, Gesammelte Schriften, Band V.1, Das Passagen-Werk.

While [North American cities] inevitably offer complex ecologies of public, private and semi-private space which are not entirely exclusionary –and some are designed to link more favourably to public streets and transit systems– very often, the primacy of the interiorised city works to residuals the traditional street.

Stephen Graham, Vertical.

Some of the largest interior cities have been built in cities with particularly extreme climates. Indeed, the 18-km system of skywalks in Minneapolis is so extensive that its various routes are coloured and named like subways line to minimise confusion.

… a motivation […] were the advantages to real estate developers or the ability to connect large systems of multilevel car parking garages directly to commercial or retail space.

Stephen Graham, Vertical.

Impressed by the emerging modernist experiments in Europe, North American master planners in the 1960s also embraced the idea of the multilevel city as a radical means of renewing and decongesting decaying urban cores so they could accommodate mass automobile use and compete with the burgeoning malls in the suburbs.

Stephen Graham, Vertical.

Der verschiedenen Berliner Passagen ist zu gedenken: der Kolonnaden in der Nähe des Spittelmarkt (Leipziger Strasse), der Kolonnaden in einer stillen Strasse des Konfektionsviertels, der Passage, der Kolonnaden am Halleschen Tor, der Gattern als Eingang zu Privatstrassen.

Walter Benjamin, Gesammelte Schriften, Band V.2, Das Passagen-Werk.