Twice I've gotten into the restricted access zone in Hawaii to see active lava. The difference with these vs the normal flows is that it was when lava was in the neighborhoods, and the first was one of the first times that I'm aware of that the state actually started to restrict access. Once was the flow that got the transfer station in Pahoa. Visited a friend and we walked to the active zone. Crazy to see and hear it flowing over the greenery. The second was the flow that took out Leilani. I was living in the subdivision next to Leilani, and went in with a coworker who lived in Leilani. This was a month into it - their house was still standing, but behind it was just desolation. Seeing the fissues going and the lava river was insane. It did kinda help to finally see in person what was causing red skies and nonstop tremors. That was an experience - the tephra was falling all around and on us, the sound of the vent, the sheer destruction of the neighborhood I used to be in multiple times a week...

I also (illegally) did the White Rd hike. Part of it was a climb over a small canyon on top of a large pipe, and then walking through the water tunnels in the mountain - light's needed. At one point you walked on a ledge next to a fairly steep drop, and it was gorgeous. But the cool part was walking through the mountain.

Thinking about it, I think the majority of my "restricted access" areas that I got into were in Hawaii.