Walk down to the harbour from Karl Johans gate and two square brick towers fill the sky long before you reach the water. Oslo City Hall, Rådhuset to locals, is the building most visitors photograph first and understand last.
It looks heavy from the outside, almost fortress-like. Step inside, though, and it turns out to be one of the most generous public buildings in Scandinavia: free to enter, covered wall to wall in murals, and still the working seat of the city council and administration.
A city hall that took 35 years to build
Oslo had made do for centuries. The old town hall of 1641 still stands at Nedre Slottsgate 1, a modest house from the years after the great fire, when Christian IV moved the city to the foot of Akershus Fortress.
By the early 1900s the administration was scattered across rented offices. Competitions for a new hall were held in 1876 and 1898, but neither design was ever built because the money was never there.
The push that finally worked came from Hieronymus Heyerdahl, who had just stepped down as mayor in 1915. During the 1914 Jubilee Exhibition he had noticed that the capital had nowhere dignified to receive its guests, so he organised a new competition.
Architects Arnstein Arneberg and Magnus Poulsson won it in 1918. Funding stalled again, and over the next decade the two kept reworking the plan, adding the twin office towers that now define the skyline.
Pipervika: the harbour slum that made way
The site they chose was Pipervika, a crowded, run-down quarter of small houses, workshops and waterfront sheds just west of the fortress. Clearing it was part of the point. The city wanted a new face toward the fjord.
Whole blocks came down, and the old Tivoli amusement park closed as land around the site was rezoned and sold to help pay for construction. King Haakon VII and Crown Prince Olav attended the foundation stone ceremony in September 1931.
Real building work began in 1933, and the brick shell was finished in 1936. A few office floors were already in use when Germany occupied Norway in April 1940, and the project slowed to a crawl for the rest of the war.
Work picked up again after liberation. Rådhuset was officially opened on 15 May 1950, timed to celebrate Oslo's 900th anniversary.
If you want to see the waterfront the building helped reshape, our walk through Aker Brygge picks up the story a few hundred metres to the west.
Why brick, and why it divided opinion
By the time it opened, the style already felt old. Architects across Europe were moving to steel, glass and concrete, and a monumental brick civic building looked like a relic of the 1920s.
Its roots are Nordic. The jury that picked the winning entry included Ragnar Östberg, who built Stockholm City Hall, and Martin Nyrop, who designed Copenhagen's, and the Oslo plan clearly owes something to its Swedish neighbour.
The bricks themselves are oversized, about 27.5 by 13 by 8.5 centimetres, closer to medieval brick than to anything in a 1930s builder's yard. They were made locally at Hovin Teglverk.
The towers are 63 and 66 metres tall. Opinions softened over the decades, and in a popular vote run by Aftenposten, Oslo residents chose City Hall as the capital's structure of the century.
Art on every wall
Inside and out, Rådhuset is really an enormous art commission. Decoration competitions began in 1937, and eight painters and seventeen sculptors were eventually hired. Most of the work was done by 1950, though the sculpture park took until the 1960s.
Outside, look for Dagfin Werenskiold's painted wooden reliefs facing the square, which retell stories from the Poetic Edda. Anne Grimdalen's Harald Hardråde rides across the west wall, and Per Palle Storm's six figures on the harbour side honour the workers who built the hall.
The Main Hall is the room people come for. It measures 31 by 39 metres and rises about 21 metres, with marble underfoot and murals by Henrik Sørensen and Alf Rolfsen on the walls.
The paintings tell a crowded story: working life between the wars, the growth of trade and the labour movement, the royal family, the patron saint St. Hallvard, and the years of occupation.
The Munch Room holds Edvard Munch's large painting Life, and it doubles as the city's civil wedding room. The semicircular council chamber is panelled in oak and hung with a tapestry of St. Hallvard and the seven virtues, meant to keep politicians mindful of their duties.
The Nobel Peace Prize ceremony
Every year on 10 December, the anniversary of Alfred Nobel's death, the Main Hall is turned into the stage for the Nobel Peace Prize ceremony. A podium is built at the far end of the room for the laureate and the Norwegian Nobel Committee.
The royal family and the prime minister attend, and the laureate receives the medal and diploma in front of the murals. That is why the building closes to visitors for several days around the ceremony each December.
Across the square, the Nobel Peace Center fills the old Vestbanen railway station of 1872. It opened in 2005 and tells the stories of past laureates, so the two make an easy pairing on a short visit.
Visiting Oslo City Hall
Rådhuset is open to everyone and there is no ticket. The city lists opening hours of 09:00 to 16:00 Monday to Saturday, and the building is closed on Sundays.
All visitors pass through a security check at the entrance, and there can be a short queue on busy days. Because the hall is still a working political building, parts of it may be closed for events even when the doors are open, so check the closure dates on the city's site before you go.
Private guided tours last about 45 minutes and can be booked in Norwegian, English or German for groups of up to 30. The price is set per group rather than per person, which makes them good value if you are travelling with friends or a class.
Bring patience for the art rules. Food and drink are not allowed in the halls, and staff ask visitors not to touch painted walls, frames or display cases.
Listen for the bells
The east tower holds a carillon of 49 bells, the largest in the Nordic countries. The heaviest weighs four tonnes and the smallest just 14 kilos.
The bells play a short melody every hour from 07:00 until midnight, and the tunes change with the seasons. Recent autumn selections have run from Grieg's Morning Mood to Dolly Parton and the theme from 'Allo 'Allo.
For a proper concert, come on a Sunday at 15:00 in June, July or August, or at 11:00 on the first Saturday of the month for the rest of the year. A city carillonneur plays for about 45 minutes, and the whole harbour becomes the audience.
Making a morning of it
City Hall sits at the meeting point of several classic Oslo walks. Rådhusplassen opens straight onto the piers, and in summer the boats to Bygdøy and the inner islands leave from quays a few minutes' walk away.
Our guide to Oslo's island ferries covers the short crossings to Hovedøya and Langøyene if you want to swap brick for beaches after your visit.
To the east, a five-minute walk along the quay brings you to the walls of Akershus Fortress, the castle that has guarded the harbour for 700 years and the reason the city ended up here at all.
Start with the murals at opening time, catch the bells on the hour, and you will see why a building that once looked out of date has become the place Oslo chooses for its biggest occasions.
About Sofia Berg
Sofia Berg is a lifelong Oslo resident and travel writer with a passion for uncovering the city's hidden gems. She has been exploring and writing about Oslo for over ten years.