[KuRoregioNka]

Many interesting theories, from totally bogus to end of the world as we know it!

I do have a question for those who say it is venting from underground tunnels; has anyone hearing these sounds tried to follow them to their source? This should not be that hard, just keep going in the direction where it gets louder. A venting tunnel exit should be a physical place one could lay eyes on, correct? Or, am I missing something here? for what ever reason, I have yet to see such an investigation attempted.

If, on the other hand, the sound's direction cannot be ascertained, perhaps this means it is coming from above or below and cannot be specifically determined. This could have many implications from a non-physical source (other dimension) to a source underground or above that is hidden (space itself, UFOs, earth faults shifting, etc.) If these sounds are being heard repeatedly in certain places, it seems like more could be done to investigate.