A demonstration of natural reverb in 15 different places

The Wikisinger (screengrab via YouTube
Joachim Müllner (a.k.a. "The Wikisinger") recently shared a video of himself performing an original song in 15 different places, experimenting with reverb, delays, and reflections — the idea behind the video is to show that every room, building, space you enter has its own unique sonic properties.
There is no artificial reverb applied to the recording — it's all natural, and it's an illuminating look into the impact of varied environments on sound.
The Austrian production company behind the video — Touché Videoproduktion — created a similar experiment a couple of years ago with a video featuring "The Wikidrummer."