Den Blå Planet – National Aquarium Denmark

A whirlpool of glass and steel by the Øresund

Den Blå Planet greets you as a dramatic swirl of metal and glass, curling towards the sea like a vast whirlpool frozen in motion. Clad in shimmering aluminium panels and set right on the Øresund shoreline, the building feels like a piece of modern sculpture as much as an aquarium. Its five “arms” radiate from a circular hub, guiding you into different aquatic worlds while always keeping you oriented around the central core. Large panoramic windows open towards the strait and Copenhagen Airport, so aircraft silently cross the sky above the water’s edge outside while sharks cruise the depths inside. The overall impression is of stepping into a purpose-built underwater universe where architecture, light and sound are carefully choreographed to keep your focus on the life beneath the surface.

From Ocean Tank thrills to secret reef corners

At the heart of the aquarium lies the Ocean Tank, a multi-storey basin holding millions of litres of salt water. A gently sloping tunnel runs straight through it, giving you the classic “fishbowl” sensation as hammerhead sharks, rays and schools of silvery fish glide overhead. Moving platforms and broad viewing windows allow both children and adults to linger without feeling rushed. Around this centrepiece, smaller but finely themed tanks reveal different marine habitats: delicate coral reefs dotted with clownfish, cold Nordic seas with cod and flatfish, and rocky coastal zones where eels peer from crevices. Interpretation focuses on behaviours and ecosystems rather than lists of species, so it is easy to understand how these environments function and why they are under pressure.

Rainforest humidity and rescued sea otters

One entire wing is dedicated to a lush indoor rainforest, where warm, humid air, dripping foliage and the calls of exotic birds create an instant change of climate. Here you can spot freshwater fish, reptiles and amphibians, as well as free-flying birds weaving between branches. Elevated walkways and low viewing points keep the experience engaging from different heights. Just outside, in a dedicated outdoor habitat, live some of Den Blå Planet’s most charismatic residents: sea otters. These animals have been rescued from the wild and given a carefully designed environment of pools, rocks and enrichment toys. Watching them twist through the water, crack open shellfish or rest on the surface adds a distinctly North Pacific note to this Danish shoreline.

Hands-on encounters and daily animal feedings

Den Blå Planet places strong emphasis on interaction and learning through doing. Touch pools let you feel the rough armour of a crab or the smooth glide of a ray under expert supervision, with staff on hand to explain anatomy, behaviour and safe handling. Younger visitors are gently encouraged to explore with all their senses, from peering through magnifying lenses to following illustrated activity trails. Throughout the day, scheduled feedings and short talks animate different tanks: rays and sharks racing for food in the Ocean Tank, piranhas snapping up their meals in the rainforest, or curiosities like electric eels and moray eels getting their turn. Simple explanations of adaptations and food chains make these sessions accessible even if you are new to marine biology.

Behind the scenes of a high-tech “fish hotel”

What you see in the exhibition halls is only part of the story. Behind the aquarium glass lies an intricate network of pumps, filters, chillers and life-support systems that keep thousands of animals healthy. Specially designed back-of-house tours reveal this hidden infrastructure, from feeding bridges above the tanks to quarantine areas and research facilities where new arrivals acclimatise. These insights underscore how resource-intensive it is to recreate ocean conditions on land, and they link naturally to broader themes of sustainability. Exhibits and educational programmes highlight how climate change, pollution and overfishing affect marine life, positioning Den Blå Planet as both an entertaining attraction and an informal science centre focused on the world’s oceans.

Seasonal outdoor play and lingering by the water

On bright days, the experience extends into the open air. A water-themed playground and shallow channels invite children to splash, dam and experiment, while outdoor basins and a wild pond area showcase the smaller creatures of local freshwater habitats. Benches and low sea walls along the edge of Øresund offer one of the more peaceful coastal viewpoints near Copenhagen, with big skies, passing ships and a constant play of light on the water. Inside, cafés and seating zones are woven between exhibition spaces, so you can pause without fully leaving the atmosphere of the aquarium. Combined with flexible opening hours and evening events during peak seasons, Den Blå Planet easily fills anything from a quick two-hour visit to a full day immersed in the rhythms of life below the surface.