Snorkel at silfra fissure in the unesco listed thingvellir national park and visit incredible golden circle attractions on this day trip from reykjavik after leaving the capital head to the national park and snorkel in the clear waters of silfra fissure a natural rift between the north american and european tectonic plates then explore geothermic valley of haukadalur by minibus stopping to see the famous geysir hot spring and gulfoss waterfall two highlights of the golden circle