Haderslev Garrison Museum.
OBS - it is currently not possible to visit the Garrison Museum, since the museum and exhibits are moving to a new location.
At Haderslev Barracks you find a small museum that tells you the story of the Schleswig Infantry. The museum tells the story of the garrison in Schleswig, at Kronborg and in Sønderborg and Haderslev. You can see the Duke-, Schleswig-, Kronborg- and Haderslev rooms as well as the April 9th room. Here, you find canons and Nimbus bikes used on April 9th 1940.
The museum is open on Tuesday and Thursdays from 11AM to 2.30PM for booked tours. Admittance is free. You can book your tour by calling +45 72 81 36 86.