We have visited another colorful geothermal area is Seltún, which is located beneath Sveifluháls, on the Reykjanes peninsula in Southwest Iceland. Seltún is located some 40 km away from Reykjavík. At Seltún we saw both solfataras and fumaroles, bubbling mud pools and steaming hot springs. On the east side of the road, there are two big mud pools. They are called Fúlipollur or “Foul smelling puddle” as they stink of sulfur. A short distance from Seltún geothermal area we found the explosion crater Grænavatn – “Green Lake”. The lake, which is 46 meters deep, gets this beautiful green color from the crystals and hot spring algae in the lake.