The Invisible Forest


Invisible Forest


In a nutshell

Imagine if trees gave off Wi-Fi signals. The map is an experiment in visual representation with a poetic, rhetorical dimension. How would the city landscape change if there was a tree planted for every Wi-Fi access point activated? The large print (100 × 110 cm) is a visualization showing in five degrees of density the distribution of Wi-Fi APs as if they were trees within the city of Milan. Signal coverage is represented using standard visual models of a woodland forest.


Imagine if trees gave off Wi-Fi signals. We would be planting so many trees that we'd probably save the planet and be connected everywhere we went! But what would happen if the inhabitants of a city put their fundamental nourishment — oxygen — at the same priority as they (already) do for Wi-Fi signals? How would the city landscape of Milan change if there was a tree planted for every Wi-Fi access point activated? My answer is that the city would be a thoroughly proper forest.

The "Invisible Forest” is the one that has already trapped us in. It surrounds us, and even if we do not realize it, it is extremely hard to escape. In some parts of the city, the forest is frighteningly thick, and yet we cannot see it. The visualization is a hypothetical satellite photograph in which the "Invisible Forest” manifests itself.

  • The Invisible Forest exhibition
  • The Invisible Forest detail


To achieve this map, I took into consideration many factors. First of all, the number of access points and their distribution across my geographical study area were provided by Skyhook Wireless, a mobile location services company with a reference network composed of over 2 billion Wi-Fi access points in most major metro areas in North America, Europe, Asia and Australia. The dataset they generously shared with me contains information about 1,122,331 Wi-Fi access points. These data were used to generate the heatmap, the main element of the visualization.

Another important part of the project is the urban canopy already present in the city of Milan. Data about green areas can be downloaded freely from the Milan Open Data portal. These data are visualized to compare “The Invisible Forest” to the existing urban canopy.
Finally, the map of the city, buildings and streets, were collected on OpenStreetMap.

  • The Invisible Forest data layers The Invisible Forest data layers

Design process

An important element of my methodological design is how I configured the heatmap. As I was reviewing the data on Wi-Fi signals, I realized it could be important to research the nature of the phenomenon to be visualized. I researched common domestic routers and the average signals radius for each type and then calculated the coverage area for each type. I then studied the standard models of woodland forest representation to determine the interval thresholds that would be applied to the areas covered by the various densities of Wi-Fi signals as if they were areas covered by trees crowns. This way, the representation can be calibrated by the Wi-Fi signals coverage and then correlated to the standard models of visual representation of a woodland forest, which is the narrative metaphor adopted.

  • The Invisible Forest design process
Here I was manually setting up layers of data for final layout

Interestingly enough, the "Invisible Forest” opens up over the low-signal-density areas and these correspond almost perfectly to the public parks of Milan! Nevertheless, this does not necessarily mean that the parks are Wi-Fi free, this is unlikely actually. It means that the density of Wi-Fi access points in those locations does not reach the first density threshold to be considered as forest if it were the density of trees. This is why I decided to represent the urban canopy as bodies of water, as lakes hidden in a forest.

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  • invisible-forest
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  • invisible-forest


The project is labeled both ‘academic’ and ‘personal’ because it was part of an individual assignment but with special directions: the artwork is part of the “infopoetry” exploration promoted by DensityDesign Research Lab. As a student of this lab, I was asked to produce a visual representation experimenting with the rhetorical dimension of data experiences, focusing on poetry — in the sense of poiesis — as a design approach. We were given freedom to experiment with any format, medium and materials, as well as stories, narrative and metaphors. This is why this project feels personal — because I was able to select the subject, the metaphor and produce the piece from start to finish on my own.
More on “infopoetry”.


The artwork was presented during the DensityDesign Open Day on February 28th, 2017, and remained on public display for the whole duration of the following exhibition inside the main building of the Design School of Politecnico di Milano.

Tech specs

Print: 100 × 110 cm (39.4 × 43.3 in)

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