In some years we have, at this time of year, rains with a lot of dust (fine sand) coming from North Africa, from the Sahara desert.
Everything is "dirty" like swimming pools, cars, terraces, balconies, etc.
This is a small temporary pool that needed cleaning and someone left a message "from the sahara desert, with love". In fact, these sands get dirty, but they also bring important nutrients to the plants. (Note: The image has been edited for high contrast, so you can see the footprints and the design, it looks dirtier than it is)
