Reverse graffiti
en.wikipedia.org
en.wikipedia.org
The tunnel's walls are covered in white tiles, but are all black because of the cars' pollution. The graffiti goes in two parts (written in French), facing each other:
* "LE MAL PROPRE" - meaning "the shoddy" has been written by cleaning the tiles composing the letters, hence white letters over a black background.
* "LE BIEN SALE" - meaning "the pretty dirty" uses the opposite technique: the tiles outside the shape of the letters have been cleaned - black letters over white background.
The graffiti really plays around the concept of mirroring: * by the way how the words are revealed: cleaning the letters or their surrounding
* by the play on words in the two commonly used expressions: "mal" - badly - being the opposite of "bien" - well -, and "propre" - clean - being the opposite of "sale" - dirty:
* "mal" has a negative connotation and is used with "propre" which has a positive one.
* "bien" has a positive connotation and is used with "sale" which has a negative one.
I only found one photo of half of it online: https://www.brusselseyes.com/le-mal-propre-2014/https://www.designboom.com/art/brian-kosoff-graffiti-abstrac...
https://en.m.wikipedia.org/wiki/The_Subconscious_Art_of_Graf...
[1] https://www.google.com/maps/place/Christian+Science+Society+...
Try doing this to a Lincoln memorial, mount Rushmore or any number of "dirty" statues across europe. Those who "cleaned" the Elgin marbles remain hated down the years.
https://www.reddit.com/r/BeAmazed/comments/1auwmvz/reverse_g...
Reverse graffiti has been described by promoters as an environmentally friendly form of advertising
It could literally be called "greenwashing".
In this situation, it'd be more like buying ads for those parked domains to reflect the previous content, or whatever else.
It's subjective though, reasonable people may disagree. If someone did what you proposed and called it reverse graffiti, I wouldn't argue the point.
Also there are in theory bio ones with lichen and moss.