This is really a three-for-one deal as there is a natural pool located outside, a hot tub, and also a beautiful indoor pool in a greenhouse. At the hotel at Heydalur, there is a mesmerising pool and hot tub inside a greenhouse, in which the geothermal energy is also used to grow vegetables and fruits. And lastly, there is a natural hot tub outside the hotel, where hot water is pumped from the ground.