This rift valley has historic and geologic significance.
It was the location of the Icelandic democratic parliament from 930 to 1798, and also a site where the Mid Atlantic Ridge is exposed.
Here, the North American tectonic plate (from which the photo was taken) is spreading opposite to the Eurasian plate.
The blue haze in the background is attributed to the current Holuhraun volcanic eruption, many miles from here.