A five-minute drive away from the city of Akureyri, Iceland’s ‘capital of the North’, lies Forest Lagoon, an unprecedented geothermal spa experience, even by the country’s exacting standards. Uniquely located in the Vaðlaskógur forest, its bathing pools are heated by a natural geothermal water source discovered by chance during a tunnel excavation project in 2015.

To make the most of its unique setting, the spa’s owners, Finnur Aðalbjörnsson and Sigríður Hammer, called upon Basalt Architects. The Reykjavík-based practice was founded in 2009 by Sigríður Sigþórsdóttir, famed for her groundbreaking design of the Blue Lagoon in 1998 (see W*21). Basalt went on to design the adjoining luxury hotel and spa, completed in 2018, as well as a string of new spas and baths all over Iceland. 

Detail view of timber pavilion at forest lagoon geothermal spa in Iceland

‘The funny thing that connects most of these projects is that they are born out of accidents,’ says Hrólfur Karl Cela, a partner at Basalt. ‘I don’t think any of the clients intended to find hot water for a bath. They were trying to find hot water for municipal consumption or heating, but the water was slightly too salty, or had algae, so couldn’t be used for infrastructure systems. But it was perfect for bathing – which is the case here.’

For Forest Lagoon, Basalt Architects has created a surreal 1,300 sq ft complex that encompasses two infinity pools with swim-up bars, a cold tub, a sauna and a bistro. Facing the Eyja Fjord, the building is split into two parts – a wooden pavilion that houses a restaurant with large glass windows, and a second precast concrete structure containing changing facilities with aspects of the exposed cliff that become part of the interior. 

Misty view across Forest Lagoon geothermal bathing pool in Iceland

Embedding the spa into the mountainside and forest was a natural decision. ‘The building is very elongated to make less of an impact on the site, so you don’t have to carve the mountain away, but work with it,’ says Marcos Zotes, a partner at Basalt Architects. ‘The forest is the leading design element, so we tried to keep as much of it as possible. There are trees inside the building and in the pool that break up the mass.’

‘Bathing in a forest in Iceland is extremely rare. It’s a unique opportunity, and we wanted to emphasise that,’ adds Perla Dís Kristinsdóttir, an architect on the project. ‘We formed the lagoon around certain trees, which played a part in determining the size of the pools.’ Cela continues, ‘We also found that the white noise of the water flowing drowns out the sounds of traffic from the road. So we placed the entrance close to the stream, then tried to include as many places as possible where you can hear flowing water.’

Forest Lagoon now stands as a fully-formed destination surrounded by walking trails and biking paths. Providing access to a previously unused area, it exemplifies both a respect for the surroundings and a reverence for natural resources. §