Bergenhus Fortress Bergenhus fortress ( ) is a fortress located in Bergen , Norway . Bergenhus fortress is located in the entrance to the harbor in Bergen . This is one of the oldest and best preserved castles in Norway . History . The fortress contains buildings dating as far back as the 1240s , as well as later constructions built as recently as World War II . The extent of the enclosed area of today dates from the early 19th century . In medieval times , the area of the present - day Bergenhus Fortress was known as " Holmen " ( " The islet " ) , and contained the royal residence in Bergen , as well as a cathedral and several churches , the bishop ' s residence , and a Dominican monastery . Excavations have revealed foundations of buildings believed to date back to before 1100 , which might have been erected by King Olav Kyrre . In the 13th century , until 1299 , Bergen was the capital of Norway and Holmen was thus the main seat of Norway ' s rulers . It was first enclosed by stone walls in the 1240s . Of the medieval buildings , a medieval hall and a defensive tower remain . The royal hall , today known as Haakon ' s Hall , built around 1260 , is the largest medieval secular building in Norway . The defensive tower , known in the Middle Ages as the " keep by the sea " , was built around 1270 by King Magnus VI Lagabøte , and contained a royal apartment on the top floor . In the 1560s it was incorporated by the commander of the castle , Erik Rosenkrantz , into a larger structure , which is today known as the Rosenkrantz Tower . In the Middle Ages , several churches , including the Christ Church , Bergen ' s cathedral , were situated on the premises . These however were torn down in the period 1526 to 1531 , as the area of Holmen was converted into a purely military fortification under Danish rule . From around this time , the name " Bergenhus " came into use . Building work on the Christ Church probably started around 1100 . It contained the shrine of saint Sunniva , the patron saint of Bergen and western Norway . In the 12th and 13th centuries it was the site of several royal coronations and weddings . It was also the burial site of at least six kings , as well as other members of the royal family . The site of its altar is today marked by a memorial stone . In the 19th century , the fortress lost its function as a defensive fortification , but it was retained by the military as an administrative base . After restoration in the 1890s , and again after destruction sustained during World War II , Bergenhus is today again used as a feast hall for public events . During World War II , the German navy used several of its buildings for their headquarters , and they also constructed a large concrete bunker within the fortress walls . The buildings , including the Haakon ' s Hall , were severely damaged when a Dutch ship in the service of the German navy , carrying approximately 120 tons of dynamite , exploded on 20 April 1944 in the harbour just outside the fortress walls , but the buildings were later restored . Bergenhus is currently under the command of the Royal Norwegian Navy , which has about 150 military personnel stationed there . The fortifications Sverresborg fortress and Fredriksberg fortress also lie in the centre of Bergen . Haakon ' s Hall and the Rosenkrantz Tower are open for visits by the public . Koengen , the central part of Bergenhus Fortress is also known as a concert venue . Prominent buildings . Haakon ' s Hall . " Haakon ' s Hall " ( ) is a medieval stone hall located inside the fortress . The hall was constructed in the middle of the 13th century , during the reign of King Håkon Håkonsson ( 1217 – 1263 ) . In medieval times , it was the largest building of the royal palace in Bergen , then the capital of Norway . It was built as a replacement for older wooden structures on the site . It is the largest secular medieval building in Norway . No written records survive of the construction of the hall . According to Håkon Håkonsson ' s saga the building was not there at the coronation of King Håkon in 1247 . It does however state that it was used during the wedding celebrations of king Magnus Håkonsson and the Danish princess Ingebjørg Eriksdatter on 11 September 1261 . The hall is built in Gothic style . In addition to the great hall itself , there were two more levels , a cellar and a middle floor . The hall ' s similarity to English structures of the same time , and the fact that monumental stone building was relatively uncommon in Norway at the time , has led to an assumption that the hall was designed by English architects , possibly the court architect of King Henry III of England , with whom King Håkon was on friendly terms . The hall has been hit by several fires , the first one as early as 1266 . From the death of King Eirik II in 1299 , Bergen lost its status as the main royal residence , and from 1380 until 1814 , Norway was in a personal union with Denmark , which meant that the royal castle in Bergen gradually fell into decay . In 1429 it was captured and burnt by the Victual Brothers , but a new stone portal from the mid - 15th century shows that the hall was rebuilt after this event . Soon after that , however , as the old royal residence was transformed into a purely military fortress , the Hall was turned into a storage building . By the 19th century , its original function had been completely forgotten , and it was sometimes referred to as " the old church " . However , the 19th century saw the rise of national romanticism in Norway as the country gradually regained its independence . As a result , the independent medieval kingdom was used as a source of new national symbols to rally around . In 1840 , it was proven that the great stone building in Bergenhus fortress was , in fact , king Håkon Håkonsson ' s old feast hall . For the next half - century , its restoration back to its original function was debated . Henrik Ibsen wrote a poem in the hall ' s honor , and poet Henrik Wergeland first used the name " Haakons hall " in one of his poems . The hall was finally restored in the 1890s , and in the 1910s it was decorated with frescos with motives from " Håkon Håkonsson ' s saga " , and stained glass windows . The hall was severely damaged on 20 April 1944 , when a Dutch ship in the service of the German navy , carrying over 120 tons of dynamite , accidentally exploded whilst docked on the harbour outside the walls of Bergenhus fortress . The stone structure was undamaged , but the wooden roof caught fire and burned up . The fire also destroyed all the decorations from the first restoration . A second restoration took place in the 1950s , and the hall was reopened on 11 September 1961 , the 700th anniversary of its first use . It is now decorated more discreetly , primarily with tapestries . Haakon ' s Hall is now administered by the Bergen Museum , which also takes care of the Rosenkrantz Tower and other protected buildings in the city . The hall is occasionally used for concerts , especially choir song and chamber music , and for banquets , mainly for official functions . A popular restaurant and bar at the edge of the Columbia University campus in New York is named Haakon ' s Hall . Rosenkrantz Tower . The " Rosenkrantz Tower " ( ) is one of the most prominent buildings of Bergenhus fortress . The tower derives its name from governor ( 1519 - 1575 ) . It was during his administration ( 1559 – 1568 ) that the tower received its present shape and structure . The oldest part of the building , however , is made up of a medieval tower , known as the " Keep by the Sea " , built by King Magnus the Lawmender in the 1270s as part of the royal castle in Bergen . The keep was slightly modified c . 1520 , then extensively modified and expanded in the 1560s by Scottish stonemasons and architects in the service of Erik Rosenkrantz to attain its present form . Rosenkrantz ' building contained dungeon s on the ground floor , residential rooms for the governor higher up , and positions for cannons on the top floor . In the 1740s , the tower was converted to a magazine for gunpowder , a function it served until the 1930s . The whole building has been open to the general public since 1966 . Today , the tower serves primarily as a tourist attraction .