Have you seen these photos of the abandoned River Country water park, formerly part of Disney World in Florida? The park closed 15 years ago and nature has started to reclaim the space. Plants and trees are growing on the slides and buildings. The photos make me think of what things would look like after an apocalypse.
It's interesting to see what would happen to many of the structures we take for granted (roads, walkways, bridges) if they were not regularly maintained. It doesn't take long for things to start falling apart, or for overgrowth of trees and plants to do some serious damage.