The mission Dutch prison architect Willem Van der Sluis was tasked with was to create an outdoor excerise/sport space for the prisoners at the prison boats in Zaandam.
The decision to use geodesic domes was a solution to the balance between the demands of justice, i.e. not allowing anybody to escape, and delivering the maximum regarding the needs of the prisoners.
The space had to be easily built and easily dismantle; prisoners had to be able to see the outside world, but outsiders should not immediately recognize the structure as a prison.
The conjoined geodesic domes do not look like cages at all. But, these spaces, designed for playing sports, prevent inmate soccer or basketball players from escaping.
Van der Sluis' major contribution is the view afforded to teh inmates. Instead of regular prison yards with walls that only afford a view upwards, the domes allow prisoners to see and experience much more of the outside world.
Pierced with smaller holes at the base creating a contrast not unlike Venetian blinds, the advantage is that from within the prisoners can look outside, but do not have to worry about being viewed by passersby.
Higher up the holes get bigger, allowing more daylight in. "I tried to give it the feel of light falling through trees in a forest," Van der Sluis explains.
The structure consists of just 15 triangles that are replicated form the whole dome. It is a design that can as easily be constructed as dismantled. If the boats the structures are on are relocated, the domes will move with them.
The domes are an innovate solution to a potentially difficult problem.