Snorkeling along the Silfra Fissure.  This was a pretty unique experience as this canyon is where the North American and Eurasian continental plates meet.  It is home to some of the clearest water in the world which along with rare sunny conditions made for favorable visibility.  After hearing the water was between 2 and 4 degrees Celsius (36 to 39 degrees F) and it being 5 C outside (41 degrees F), I opted for the dry-suit option whereas Deb stayed strong and went in a wetsuit.  This afforded her the opportunity to dive down and check out the canyon a little better where I was limited to floating on the surface.  This was fine with me.  The excursion took approximately 2 hours with ~ 30 – 35 minutes in the water. The guides at Adventure Vikings were great and very accommodating.  They gave us some local knowledge of a couple other things to do in the area that we definitely would have checked out if we had more time.