#AdventureTravel: A Terrifying Trek Into the Heart of Darkness. America's 8 Scariest Hikes

I wave my hand in front of my face but I can’t see it. Just darkness like I’ve never known before. Total blindness, and the sort of terror that comes with losing one of your senses, even for a moment. I’m afraid to
take the smallest step, and when I do, I can hear the gravel beneath my hiking boot crackle.
It’s cold this far underground in Lava River Cave. Not freezing, but well below 40 degrees.
I had lost my father a few months prior. He died on a weekday in the middle of the night, and even though he was old enough for me to have seen it coming, it was still a surprise.
Months later, I’m in northern Arizona where my brother went to school. We had spent the early morning talking about dad for the first time since he passed, before I broke off on my own to explore this cavernous underground hideaway.
The mile-long lava tube just outside of Flagstaff, Ariz., (about 14 miles) was formed when a volcano in Hart Prairie erupted about 700,000 years ago. The molten rock that erupted flowed like scolding hot sludge, then cooled and solidified. The rest of the lava river flowed inside its walls and what it emptied out became this cave.