vendredi 13 janvier 2012

BARCELONA - A FRACTAL EXPERIENCE


There's one part of Barcelona where the streets pattern is shaped by the repetition of the same geometrical units : straight lines are indefinitely followed by orthogonal "squares". This is "The Eixample", the extension of the city conceived and built by Ildefons Cerdà during the second half of the 19th century.


Space pattern in the Eixample
(extension of the city thought and built by Cerdà from 1860)

The Eixample surrounds the historical cores of Barcelona (El Raval, El Gotic) on the west and south-west side, and mainly spreads between the "Avinguda Diagonal" and the "Gran via". The striking regularity of The Eixample is very distinctive on the satellite picture because it lies within two different kinds of mess :  the medieval mess of narrow streets (on the east side by the harbor), and the modern mess everywherelse where no specific organisation of space can be seen or identified (even if there are much more straight and wider streets than in the medieval mess). check below

Distinctive regular pattern of the Eixample inside the urban network

Its even more obvious like this
Schematic representation of the Eixample pattern in the city
NB : the white space is not empty but filled with urbanisation that is not represented...

You might completely  miss this detail unless you look attentively to a satellite view of the city and notice the striking regularity in the middle of the map, but it is possible to first get aware of this specific structure from the ground, by experiencing two different kinds of feeling while walking around :
First you'll find asking yourself  a bit too often  "this looks familiar, didn't I pass here earlier ?" while being sure you've been walking in one direction only, so there's no chance you could have gone "around". This is confusing for the mind until you actually admit that it is possible to be in a city that repeats itself on purpose for kilometers. It is completely normal to feel you're in the same place because in a way you are, and the only thing that changes is the nature of the stores and bars on street level. You are literally "translating", the space is homogenic.

Also, as a walker you might find a bit annoying each time  you reach one of those orthogonal places to always   have to break your straight line progression to make a detour and use the cross-walks as below : 
Walker path in the orthogonal places of the Eixample



Cerdà in Barcelona, Haussmann in Paris, they both re-ordered our lives in a very ambitious way, transforming massive parts of cities at the same time, opening wide avenues, connecting different reference points and monuments in the city, making it more coherent and "hygienic", while around the same time Auguste Comte and the positivists were theorizing the "positive age" that humanity was supposed to enter by then. It was then still possible to think about urban planning as a possible science, a discipline you could control in a deterministic way, like other things like machines and capitalist production. 

The massiveness of the changes made at once over a short period of time,  the will for structure and organisation used in city planning were going hand in hand with the trust and faith in the power of rational thinking and the idea of progress, temporaly proved by the successes of science and the spread of industrial empires.

Realizing this gets you a bit dizzy, and this fall into the depths of consciouness reach climax when you sit at this bar and the mosaic on the wall looks exactly like the street patterns outside




Which actually turns this part of Barcelona into a fractal object, defined as follow by Wikipedia  :
 "a rough or fragmented geometric shape that can be split into parts, each of which is (at least approximately) a reduced-size copy of the whole, a property of self-similarity"


AP