I took this image of Grundarfoss on a very cold morning because, well, how cool is it that the public water supply of a major city of 872 people (huge for Iceland) is a waterfall. Very cool! So cool, I could hardly hold the camera steady.
But look what I missed, at the base of the cliff just to the right of the base of the main fall: a lava tube. Now, how cool is that! But, of course, it’s a public water supply, so no snooping around there. Rats. What about the troll at the base of the hill at the left of the image. I bet they’d let me go visit it.