Blue Lagoon, Iceland
This stunning lagoon is pleasantly warm (38°C) with mineral-rich geothermal water in a middle of a black lava field. The high natural levels of silica and minerals give the Lagoon its rich blue colour. The water originates 2,000 metres below the surface, where freshwater and seawater combines at extreme temperatures. It is then harnessed via drilling holes at a nearby geothermal power plant. Groups often choose to stop for a swim here en-route to your hotel from the airport, after you have met your guide in the airport arrival hall, and boarded set off on your private coach.
If you are after a cheaper less crowded geothermal swim then check out the Secret Lagoon below which can be added to the Golden Circle Day