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Photo: User:Mahlum, Public domain via Wikimedia Commons
The German submarine base for the 13th flotilla during the German occupation of Norway (1940 - 1945). Today the bunker houses several archives, among them are the Trondheim city archives, NTNU university and governmental archives.
Dora I is a former German submarine base and submarine pen or bunker built in Trondheim, Norway. Construction of the bunker was undertaken during the Second World War. Nearby is the uncompleted Dora II. Trondheim was traditionally referred to as Drontheim in German, and the name DORA is the letter "D" in the German phonetic alphabet.
© OpenStreetMap contributors
The city library is built upon the ruins of a medieval church and some archaeological objects are on display. The building, which was built as the original city hall in the 19th century, is a remnant of the past. Also, being a library you can also borrow and read books, and it's the site of various events.
Trondheim Science Center
A center for popularizing science, has lots of exhibits, of which many are interactive. Also has a gift store. It is home to one of Norway's largest planetariums which was opened in 2017.
Kristiansten festning
A fortress on a hill overlooking the centre. Have a walk in the area for views of Trondheim one can take the bus 25 to Ankersgata, or rent a bike and use the bike lift at Trampe.
The "Church of Our Lady" also dates from the Middle Ages but was partially rebuilt after the 1708 fire.