The Vakbondmuseum is also known as the Stichting De Burcht. You’re asking why?
Well this building is so interesting that if you have any interest in architecture that you must visit.
Designed by the founder of the Amsterdam school of Architecture, Hendrik Petrus Berlage (1856- 1934), who was a forceful figure on reshaping Amsterdam into what we see now in the 21st Century. The building was created for the thriving diamond industry whose capital was in Amsterdam at the time. Now the National Trade Unions Museum (or Stichting De Burcht) has its home here.
The museum’s website offers the following description: “Inside, you’re under the illusion that you have entered the covered courtyard of a Mediterranean palace. Sunlight streams down through a double roof of yellow and white glass and, passing through glass floor tiles, penetrates as far as the basement. The walls are of yellow, white and blue glazed brick and are relieved by vaults, columns and balustrades. An enormous hanging lamp high in the glass cupola, dominates the most beautiful of Amsterdam’s staircases. In the stylish rooms, you can enjoy paintings by Richard Roland Holst, stained glass windows, wooden panelling and furniture designed by Berlage himself. You can explore as high as the tower room that offers a view of the impressive cupola construction. In the high tower, you will see a lighted window pane in the form of a diamond.”