Ways arranged in an urban whole between closed properties, generally respecting a building line, and including a roadway, reserved for vehicles and followed on both sides by pavements for the use of the pedestrians.

Vitruve (first century BC) constitute the first theorized reference about it architecture which recommends starting the composition of the streets from an octagon to mitigate the effects of eight dominant winds. It leads to a combination of eight aligned ways which delimit rectangular pieces according to an orthogonal screen
(1).

The Roman layouts are organized according to an orthogonal grid (2) where the cardo and the decumanus are the two principal streets, NORTH-SOUTH and east/west.

In the 12th century, the "rue Neuve-Notre-Dame ", 7m wide, is the broadest of Paris, the medieval streets being narrow and sinuous. As underlined by the expression "to hold the top of the paving stone"; they are made of two planes inclined towards a central channe (3). Lined with arcades, they are partly covered with projections on the frontage.
With the Renaissance, following new technical and aesthetic standards, they become again, as F Choay underlines it, "wider, rectilinear, lined with buildings which have aligned and uniform frontages " (4).

In Paris, the first public lighting appeared under Henri IV. , Sully intervened on the cross section of the streets, by promulgating an edict prohibiting the "projections and overhangs" on the frontages facing a street.

At the 18th. century, the circulatory function becomes little by little dominating. In 1768, the Parisian streets are marked, numbered and provided with pavements (1781). According to the law, the street must answer certain rules of prospective and alignment. The H/L ratio (height of the building on the way divided by the width of the latter) is instituted in 1784. All new street must be 12m (2+8+2) wide.

By amplifying the traditional principles, Haussmann reorganized Paris from 1853 to 1869, in order to meet the needs for traffic, hygiene and safety. The streets accommodate from now on all kinds of utility networks, and the carriageway gets a curved aspect (5). The Haussmann model of a street is characterized by a constant height of the buildings (17.55 m over the way), value established since 1784. Only the width can vary.
In 1867, Cerda presents, for the town of Barcelona, a project based on the network town planning. It treats on a hierarchical basis the streets according to their function. Its plan, based on a systematic pattern, distinguishes the space of the block from that of the street. It details the installation of trees and urban furniture at the crossroad (6).Hénard later, in 1910, recommended in particular buildings on a Greek key pattern to decorate the landscape of the ways(7) and he is the precursor of the modern street.

The development of transport means, starting in the 20th century, revolutionized the architectural treatment of the street. A new decree instituting for reasons of hygiene the H=L ratio, in complete rupture with the old decree imposing a 6 m street width (A). As early as in 1902 the maximum building height is fixed at 32m. The morphology of the street evolves and leads to a separation of the pedestrian/vehicle functions..
At that time the question of the landscape and picturesque of the street is also tackled, by C Sitte and R. Unwin. They treat, inter alia, topics such as the crossings, the framing of the prospects and the curved or rectilinear layouts. The street appears as a œuvre that one puts in scene according to particular urban situations (cf urban windows (8).
Corbusier (1887/1965), who represents the modern Movement, recommends the removal of the "corridor-street", symbol of archaism. For him: "the streets should not exist any more, it is necessary to create something which replaces them". He alters the traditional sense of the term "street", to indicate an interior and commercial gallery within great "dwelling units" (the interior street). Outside, it creates a landscape, made up of sights in "panoramic sequences", punctuated by isolated towers (9) (cf. panoramic sequence). The radical separation of the motor vehicle and pedestrian traffics thus produced the city of towers and large housing estates (the heights of the buildings can reach 90m), in which the street does not exist any more. Since the 70's, following the unanimous criticism of the architecture of high rise and long blocks (barres), one returns to the street as multipurpose spaces, carrying various values such as "user-friendliness, safety, tradition". In the same way, the provision of a ministerial circular imposing a street width of 8 m in the family house allotments, was abandoned as being an oversize in relation to the use of serving the buildings

Since then, a range of solutions has been proposed:
In 1973, the rue du Gros Horloge in Rouen was arranged as a pedestrian precinct
(B).
In 1991, L Krier advocates a return to the picturesque street through its project for Poundbury in England (C).
In 1995 in Paris, Ch. de Portzamparc takes again Cerda's principle of a flexible block with the concept of the "open street" which is lined with "free blocks".(D)
One rediscovers, in particular, other street shapes like the home zone (E) and the arcaded streets (F).

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Various typologies of streets can coexist, which reconcile the pedestrian walk with a regulated vehicle use, which implies action to transfer the parking of the vehicles and a treatment of the street space to make it more accessible to all. Last, the search for picturesque, which makes the city more pleasant, will be satisfied by the creation of live urban windows.

Cf. ALIGNMENT, AVENUE, BOULEVARD, CARRIAGEWAY, HOME ZONE, URBAN WINDOW, URBAN WAY, CROSSROADS, PAVEMENT, PARKING, BLOCK, ACCESSIBILITY