One reason I love London is that you can be looking out the window at a bus stop and see this:
The juxtaposition of old and new fascinates me. Rome is great this way, too, though the history there tends to be more subterranean. At one point, I realized that it wasn’t that the ruins in Rome had sunk, but rather that the city rose up, with successive layers added on top, and centuries of refuse, mud and old materials raising the level of the streets as well. Some areas were filled in with rubble to allow for fresh construction on top.
Even the posters are this way–rows of posters slathered over last week’s posters–to a depth of a couple of inches, sometimes torn away, then layered up again. in the ripped sections, you can catch glimpses of the entire entertainment history of the city. Even the books! If you look closely at the spines of medieval and early modern texts, you’ll often find the spines stiffened or covers made from strips of old manuscripts that couldn’t be scraped down and written over (which is the definition of “palimpsest” after all.)