Newly opened spa just by the fjord.
There are 8 hot springs, a steam room, and of course, the ocean for a quick cold plunge! Your admission includes the use of their paddle boards if its a nice day.
Men's and women's changing rooms, a private changing room, and not-entirely-private shower stalls. The least expensive admission option does not have any private facilities.
Sandals, thongs, flip flops, etc. are recommended as the ground from spring to spring is quite rocky.
You may also visit Hvammsvik if you don't have a rental vehicle by booking a bus transfer to/from Reykjavik!