I really like the silvers and grays in this photo above (again from about 2006). This next one was taken during full-on winter.
I found a cool website that gives the full history of the attention that has been paid to Gullfoss over the years. It is at http://www.vulkaner.no/n/gullfoss/egullfoss.html.
These last few pictures are ones that I took in 1986. Do you notice any differences in the falls in the last 21 years?