What strikes me from Mr. Colton Allen's "Urban exploration" works is this feeling of emptiness. The absence of men in an apparently man-made (and sometimes man-spoiled) environment. Really inspiring. Thanks to Lou @pickerandagrinner for getting me to know him.
This photo was taken on Oct.23rd, and I'm posting it on the 29th for the 21st... I fear it does not qualify for the challenge but I will tag it as well ;-)