A few months ago, when I was visiting the local Children's Library.
[digression]Don't ignore the children's section of libraries and bookshops. There are a lot of highly talented writers working in the field. Series you might want to try are Time Riders by Alex Scarrow (time travel sci-fi), Skulduggery Pleasant by Derek Landy (modern setting dark fantasy with a wry sense of humour), Hell's Underground by Alan Gibbons (Horror. First book is called Scared to Death) and Mortal Engines by Philip Reeve (post apocalyptic sci-fi, but long after so civilization rebuilt on different lines)[/digression]
I saw this on a nearby wall.
After some investigation I found out that this was part of the
Hastings Moths Project an urban art project. Essentially, the setup is simple. They put a stencil on a wall that has been discoloured by pollution and use a high-pressure hose to "clean" the area within the stencil. Unlike more traditional graffiti, removing it would simply involve cleaning the rest of the wall in the same way.
There are 7 sites in total and I managed to track them all down and take my own pictures as follows.
Old Town
Town Centre
North end of Town
Hidden Back Street
Bowling Green Hut
Sea Front
In the conception, the execution and the look, this is the sort of art I love.