Iceland's National Park, or "Field of the Parliament"
Thingvellir National Park is becoming well known as one of the places where HBO films Game of Thrones. Besides that cool factor, the park offers an unique view of Iceland's tribal and Viking history, even though parts of the park can feel a bit field trip -esque. Regardless, I recommend Thingvellir for a day of easy exploring, plenty of moments when you actually are in GOT's "the Eyrie" (hello, Instagram!), and for other adventurous activities like snorkeling the glacial pools (see my post on Silfra), open-road biking, or hiking to one of the area's volcanoes.