The Landmannalaugar hot springs were our favorite activity after hiking the sorrounding areas. Funnily enough, this is a free spot if you manage to cross the two creeks and do not sleep there. If you park your car before the creeks then you have to pay a parking fee. If you sleep there you have to pay the campgrounnd fee but the hot spring is included. In our opinion, staying overnight is the best as you get to enjoy the hot springs after every hike. Plenty of people take their beers to the hot spring. DO NOT MISS IT!