Ride a RIB speedboat that's faster than the wind and take to Skjálfandi Bay where larger whales swim. With 24 species of whales in the area, there's a good chance of seeing a variety of beautiful sea behemoths. The ones likely to be spotted are humpbacks, minkes, blue whales, harbor porpoises, and the white-beaked dolphin.
From April 15 to August 15 (approximately) you can take a trip to Puffin Island. Around 70% of Arctic Puffins nest around Iceland, so the opportunity is rife for wildlife lovers.