About 2km south of Kleifarvatn, the colorful geothermal area Austurengjar in Seltún (often called Krýsuvík after the nearby abandoned farm) is among the easiest to visit on the Reykjanes Peninsula. Wooden walkways cross the uneven earth and signs explain what you’re seeing. Hot steam rises from blue pools in shades of orange and yellow earth. Listen for the bubbling of mud pools and steaming sulfuric solfataras (volcanic vents), which shimmer with rainbow colors from the minerals in the earth. Smell the sulfur in the air, and hear the hissing of vents in the mud. (There are bathrooms, too.)
Just to the north, don't miss Grænavatn , an explosion crater filled with gorgeous teal water, caused by a combination of minerals and warmth-loving algae.
