Therefore:
Make a bulge in the middle of a public path, and make the ends narrower, so that the path forms an enclosure which is a place to stay, not just a place to pass through.
59i
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Above all, to create the shape of the path, move the building fronts into the right positions, and on no acount allow a set-back between the building and the path—building fronts (122); decide on the appropriate area for the “bulge” by using the arithmetic of pedestrian density (123); then form the details of the bulge with arcades (119), activity pockets (124) and stair seats (125); perhaps even with a public outdoor room (69) ; and give as much life as you can to the path all along its length with windows—street windows (164). . • .
122 BUILDING FRONTS*
. . . this pattern helps to shape the paths and buildings simultaneously; and so completes building complex (95), wings of
LIGHT (107), POSITIVE OUTDOOR SPACE (l06), ARCADES (I 19), path shape (I 21), and also ACTIVITY POCKETS ( I 24).
Building set-backs from the street, originally invented to protect the public welfare by giving every building light and air, have actually helped greatly to destroy the street as a social space.
In positive outdoor space (106) we have described the fact that buildings are not merely placed into the outdoors, but that they actually shape the outdoors. Since streets and squares have such enormous social importance, it is natural to pay close attention to the way that they are shaped by building fronts.
The early twentieth-century urge for “cleanliness” at all costs, and the social efforts to clean up slums, led social reformers to pass laws which make it necessary to place buildings several feet back from the street edge, to make sure that buildings cannot crowd the street and cut off sunshine, light, and air.
But, the set backs have destroyed the streets. Since it is possible to guarantee plenty of air and sun in buildings and streets in other ways—see, for example, four-story limit (21) and wings of light (107)—it is essential to build the front of buildings on the street, so that the streets which they create are usable.
Finally, note that the positive shape of the street cannot be achieved by merely staggering building fronts. If the building fronts are adjusted to the shape of the outdoors, they will almost always take on a variety of slightly uneven angles.
| BUILDINGS |
|---|
 |
| Slight angles in the building fronts. |
Therefore:
On no account allow set-backs between streets or paths or public open land and the buildings which front on them. The set-backs do nothing valuable and almost always destroy the value of the open areas between the buildings. Build right up to the paths; change the laws in all communities where obsolete by-laws make this impossible. And let the building fronts take on slightly uneven angles as they accommodate to the shape of the street.
| no setbacks |  |
| slight angles | |
❖ *£♦ 4*
Detail the fronts of buildings, indeed the whole building perimeter, according to the pattern building edge (160). If some outdoor space is needed at the front of the building, make it part of the street life by making it a private terrace on the street (140) or gallery surround (166) j and give the building many openings onto the street—stair seats (125), OPEN STAIRS (158), STREET WINDOWS (164), OPENING TO THE STREET (165), FRONT DOOR BENCH (242) . ... 1
TOWNS
This process can be implemented by regional zoning policies, land grants, and incentives which encourage industries to locate according to the dictates of the distribution.
| % |
|---|
 |
• •
■
■ ♦
«
towns of 1,000,000-250 miles apart towns of 100,000 - 80 miles apart towns of 10,000 - 25 miles apart towns of 1,000- 8 miles apart
As the distribution evolves, protect the prime agricultural land for farming—agricultural valleys (4); protect the smaller outlying towns, by establishing belts of countryside around them and by decentralizing industry, so that the towns are economically stable—country towns (6). In the larger more central urban areas work toward land policies which maintain open belts of countryside between the belts of city—city country fingers
(3). • •
| 123 PEDESTRIAN density* |
|---|
 |
596
. . . in various places there are pedestrian areas, paved so that people will congregate there or walk up and down—promenade
(31), SMALL PUBLIC SQUARES (6l), PEDESTRIAN STREET (lOO),
building thoroughfare (ioi), path shape (121). It is essential to limit the sizes of these places very strictly, especially the size of areas which are paved, so that they stay alive.
Many of our modern public squares, though intended as lively plazas, are in fact deserted and dead.
In this pattern, we call attention to the relationship between the number of people in a pedestrian area, the size of the area, and a subjective estimate of the extent to which the area is alive.
We do not say categorically that the number of people per square foot controls the apparent liveliness of a pedestrian area. Other factors—the nature of the land around the edge, the grouping of people, what the people are doing—obviously contribute greatly. People who are running, especially if they are making noise, add to the liveliness. A small group attracted to a couple of folk singers in a plaza give much more life to the place than the same number sunning on the grass.
However, the number of square feet per person does give a reasonably crude estimate of the liveliness of a space. Christie Coffin’s observations show the following figures for various public places in and around San Francisco. Her estimate of the liveliness of the places is given in the right-hand column.
Sq. ft. per person
Golden Gate Plaza, noon: 1000 Dead
Fresno Malclass="underline" 100 Alive
Sproul Plaza, daytime: 150 Alive
Sproul Plaza, evening: 2000 Dead
Union Square, central part: 600 Half-dead
Although these subjective estimates are clearly open to question, they suggest the following rule of thumb: At 150 square feet per person, an area is lively. If there are more than 500 square feet per person, the area begins to be dead.
BUILDINGS
Even if these figures are only correct to within an order of magnitude, we can use them to shape public pedestrian areas—• squares, indoor streets, shopping streets, promenades.
To use the pattern it is essential to make a rough estimate of the number of people that are typically found in a given space at any moment of its use. In the front area of a market, for example, we might find that typically there are three people lingering and walking. Then we shall want the front of this market to form a little square, no larger than 450 square feet. If we estimate a pedestrian street will typically contain 35 people window shopping and walking, we shall want the street to form an enclosure of roughly 5000 square feet. (For an example of this calculation in a more complicated case—the case of a square in a public building that has yet to be built—see A Pattern Language Which Generates Multi-Service Centers, Alexander, Ishikawa, Silver-stein, Center for Environmental Structure, 1968, p. 148.)