This is the ultra high end version of the regular Blue Lagoon. It's an amazing 5-star hotel and you can also buy day access to the pool and spa. The pool of The Retreat is carved through the lava field with many secluded areas. You are likely to find areas where you are all alone, very different to the regular blue lagoon. Don't miss out on the spa and 4-step ritual, it's a must try. Entry fee depends on season but is usually from €300 for 2 guests.