The true nature of “the tunnel”

Level 4 – Charter Web

I believe this is in reference to the claim that people see a light at the end of a tunnel after a near death experience. The true nature of the the tunnel is an interesting thought experiment, suggesting that the tunnel is something other than darkness. Perhaps is an actual place, space maybe, or maybe a tunnel much like a subway; a tunnel used for traveling. What do the walls of this tunnel look like? What are is it made out of? Do we all travel through the same tunnel or do we each have our own tunnel we will travel through at death?

LINKS
https://www.livescience.com/16019-death-experiences-explained.html