What defines spatial qualities and how can one visualise them? Through context, spatial qualities emerge and get altered, like the city wall: the structure remains, but the context in which one observes those historical landmarks has been radically transformed and with it the perceptual experience. In addition, presentation influences this spatial perception as well. Nowadays, a wall is been reduced to a surface; earlier a landmark impregnated with architectural history. During the depth examination the artist stood suddenly in the middle of the masonry; she understood it suddenly as a three-dimensional architecture.
What spatial qualities define a wall? In this aspect the Petersdoms wall disintegrates; the space becomes wall and the wall becomes space, house, settlement, city.