Snøhetta have revealed designs for the international architects' latest leisure project – the first underwater restaurant to open in Europe.

Located at the southernmost point of the Norwegian coastline, the restaurant, called Under, will double as an aquarium and marine research centre.

Snøhetta's design is inspired by the country's rocky coast, with a monolithic structure breaking from the surface of the sea to rest on the craggy shoreline.

The bottom of the building will rest directly on the seabed, 5m (16.4m) underwater. To withstand pressure and shock from the rugged conditions, the walls will be a metre thick and formed of concrete. The coarse surface will invite mussels to attach themselves to the restaurant, gradually creating an artificial reef “that functions dually to rinse the sea and naturally attract more marine life to its purified waters”.

The seafood restaurant, run by Danish chef Nicolai Ellitsgaard Pedersen, will be able to accommodate up to 100 guests. They will be led on a journey from the shore and into the building, with plaques along the route providing information about the region's marine history.

From the entrance, they can descend three levels, through a wardrobe area, champagne bar and finally the restaurant itself.

Here, a vast panoramic acrylic window will offer a view of the seabed as it changes throughout the seasons and varying weather conditions.

The transition between the shoreline and the ocean will be articulated through the use of colour and materials. The bar will be characterised by a subdued palette evoking the sediment of shells, rocks and sand, while the dining room will “be submerged in darker blue and green colours inspired by the seabed, seaweed and rough sea.”

Researchers from Norwegian marine centres will use the site to explore whether fish behave differently throughout the shifting seasons. They will also create conditions on the seabed that allow fish and shellfish to thrive in proximity to the restaurant.

In a statement, Snøhetta said: “In Norwegian, the word ‘under’ can just as well be translated into ‘wonder.’ More than an aquarium, the structure will become a part of its marine environment.

“Through its architecture, menu and mission of informing the public about the biodiversity of the sea, Under will provide an underwater experience inspiring a sense of awe and delight, activating all the senses – both physical and intellectual.”