Deep Below the Surface
There are some stunning lava tube caves over here. This is Cave Raufarhólshellir.
The cave is particularly high from ground to ceiling, as you can see, being one of the highest in Iceland.
The tungsten light that you can see deep inside the tunnel comes from other travelers. They had head torches, but I had a hand torch with blue LED bulbs (you can see my shadow in the front of the image)
The cave was illuminated by repeated flash gun shots, as I tried to advance as rapidly as possible on the rocky uneven surface of the cave.
This was quite an experience! For me, photographing in caves is the most demanding photo shooting that I can think of. Or quite.
Exif: ISO 500 ; f/2.8 ; 25 sec ; @14mm (image cropped)