This picture was made on the most impressive object I have seen so far: an old papermill in Sauerland, Germany. One part of the building (approx. established in the 1840s as a cloth factory) was drystone walled, the other part was made with modern bricks.
The factory was abandoned in the 1970s and nowadays there are growing some birches on the rooftop. The roots of those trees are visible everywhere, even on the ground store between the joints.
On this photo vegetation and electric cables are growing out of the wall. With the years the control box floated down entwined by vegetation, which ist carrying it.
Below you find a few other impressions from there.
Take a look at the whole picture set on https://www.flickr.com/photos/g3sus/sets/72157624922929077/with/5031234053/