Man-made walls provide habitat for animals and plants.
Here a woodlouse Porcellio scaber returns to its shelter..
..a hole in a brick wall beside a footpath I often use.
The brick and mortar surfaces are also encrusted with lichen such as is found on natural rocks.
A number of woodlice had all emerged in a few moments from hiding places on this wall as I watched, and moved away in various directions. I was surprised to see them roam like this in bright daylight, as they usually shelter in dark damp places.
Woodlice are crustaceans, not insects.
Kinghorn, Fife, Scotland. 1st July 2009, around midday BST.