In this picture you can see the geothermal area "Hverarönð" which can be found east of lake Mývatn. With some awesome looking boiling mud pits this truly is a fantastic place your eyes and ears. Unfortunately not for your nose.... yummy yummy here comes the hydrogen sulfide. Make sure you breathe through some of your clothes... otherwise you will suffer big time :D
Nonetheless a really fantastic place and a must visit whenever you go to Iceland!