https://3speak.tv/watch?v=orestistrips/sjvapgrq
When was it the last time you made a test for echo? One of the weirdest places to do so is the one I chose today, a silver mine of the 19th century.
Here is the location: https://goo.gl/maps/D3GYkq9ReXBwGg8c8
I am tempted to come back one day with my guitar! More material on that place coming soon.