
While not really a camping trip, it did occur in the mountains near Arrowhead -- way inside the mountains. Today, Andy and I went 4,000 feet inside the mountain on an incredibly rare tour of the construction of an eight-mile long tunnel from Devil's Canyon to Waterman Canyon.
The tunnel is being built by the Metropolitan Water District to move 10,000 cubic feet of water per second to the Diamond Valley Reservoir. We got the tour because of my volunteer work with the US Forest Service.

The engineering of this project is too fascinating and too involved to describe here, but should make for a great campfire discussion if you get me started. The Waterman end of the tunnel was too busy for a bunch of tourists to get in the way. They were dragging a dozen 60,000 pound, 12' diameter tunnel sections through a 19' diameter bore. We went through the Devil's Canyon end, walking almost a mile through the pipe, past various stages of grouting, forming and welding, to this pipe placing machine that places the smaller pipe into exact position. We kept looking for Mike Rowe and the Dirty Jobs crew. What an amazing experience.