sparkling silfra on a snowy day in iceland

adventure american ancient blue boundary brave cold day detail dive diving eurasian europe experience exploration extreme famous geology geomorphology heritage historic iceland icelandic icy lake national natural nature nordic north northern park parliament plate plates popular prehistoric rift scandinavia shiny silfra site snow snowy sparkling tectonic tectonics temperatures terrain thingvellir travel trip turquoise unesco unique world aingvallavatn aingvellir