Years ago, I was on vacation in Hawaii and went on a hike up an extinct volcano (no real threat aside from the "threat" of the hike alone).
The hike wasn't the hardest I've ever done, but I came to this point where I had to traverse through a narrow tunnel that was poorly lit with uneven ground.
The entire time I was going through it, I was terrified because it was pitch black and I had to feel the walls to make my way through and I almost fell several times.
I eventually made my way to the end and finally saw light so I found a place to rest and I was thinking "WTF that was so dangerous how do they let average people go on that hike?" and I took off my hat and sunglasses to relax and embrace my survival and that's when I realized that it was only pitch black because I was wearing my sunglasses the entire time.