First off, get beta and directions from a local who is confident they know where this is. The pictures look worth it! This location seems to be the general consensus. For this location, you'll drive down 910 to the end, go over the dam, make a right onto the dirt road and when you come to a 4 way dirt intersection in 2 km, make a left. Go over the river or get out at the river and hike the last 400m. Laugarvallalaug‏ Natural Thermal pool is a true oasis in the middle of nowhere. Close to the ruins of the deserted Laugavellir Farm there is a geothermal stream that flows into a warm little waterfall, falling into a small pond at the bottom of it, namely Laugavallalaug‏ Natural Thermal pool. There the stream has been dammed, turning the warm water into a perfect pond for bathing, with the waterfall itself serving as a shower. Please remember to check the water before diving into it, since it might at times be a little too warm. How to get here: Drive down 910 past the hydro plant, make a right (which is a rough road) and after 2km (in theory) you'll come to a dilapidated hut with a grass roof, and just a few meters further along the road is a dammed stream. Down below the bank is where this stream runs off the cliff, creating a natural warm shower/water fall and pool.