Here, ina a beautiful spout in a valley under the most notorious Icelandic volcano Eyjafjallajökull is situated the oldest geothermal swimming pool in Iceland built in 1923. Just few steps from the pool is glacial river where you can refresh yourself before entering the thermal water of Seljavallalaug. Highly recommended!:)

How to find Seljavallalaug geothermal pool:

Seljavallalaug geothermal pool is located on the south coast of Iceland in between mountains approx. 6 kilometers (4 miles) west of Skógafoss waterfall. Turn of the Ring Road here (GPS: 63.535282, -19.637809) to the road nr. 242. and go for about 2,5 kilometers (1,5 miles). There you´ll find a parking lot (GPS: 63.558912, -19.622305) and from there on, you have to walk to the geothermal pool for about 10-15 minutes. 
GPS coordinates of  the Seljavallalaug geothermal pool: 63.565504, -19.607961 Take me there!

Seljavallalaug geothermal pool photos: