Rotterdam was destroyed during WW2 and it was rebuilt keeping in some parts the common Dutch architecture, but the main landscape consists of sky scrapers and modern buildings. It’s not a surprise to say that the cubic houses from Blaak area represent a top attraction for tourists of all kinds. The passage called OverBlaak gives an impressive view of the houses. The form of the houses arouses a lot of curiosity and the head is starting spinning a little bit due to the 45 degree angles.
One of the houses is opened for visits for an cost of 3e (price 2017). It will be a little bit crowded as the house is not spacious, but it is quite interesting to convince yourself that the floor is flat. The second and last floor is like a sauna in the summer, but you can see the peaks of the other houses, resembling mountains.
The houses were designed by architect Piet Blom and are considered a solution in optimizing the space as it is enlarging the common public space. A nice article about them you can find here.