Portuguese practice KWY.studio worked with artist studio Superflex and local schoolchildren to create this series of five pink marble play sculptures in Billund, Denmark.

Named Play Contract, the structures were designed to be "informed by children's thoughts about play".

Created for Danish organisation Capital of Children, each of the five small marble structures incorporates covered areas, steps and pathways to reframe how both adults and children interact with the surrounding landscape.

"Most [playgrounds] are designed and built based on grown-ups' notions of children and how they should behave," explained Superflex.

"With Play Contract, the balance of power is tipped, and now it's the children's turn to devise a playful space for themselves and grown-ups," it continued.

"What kinds of play equipment should be in such a playground? What kind of playground would they like to have when they grow up?

The play structures were devised at a workshop where 122 schoolchildren used pink Lego bricks to create models.

These models were then analysed to determine a range of forms, such as gate, amphitheatre and tower, along with a series of proposed uses, such as climb, swing, sit, slide and jump, which informed the final designs.

"The process was to generate a unique result from the children's models while retaining everyone's ideas," said KWY.studio.

"All models were carefully traced, and multiple combinations were layered and intersected into new configurations."

"At the end it is as if every model of every child is there composing a city, of which parts have been carefully uncovered for what is to be a new everlasting future," it continued.

The studio built the five structures from pink marble in order achieve a feeling of "timelessness", which was intended to evoke a sense of curiosity around who designed the structures and why.

"Visits to quarries and workshops informed how the material was to be used, retaining both natural traces as well as man-made processing imperfections," said the studio.

"Finishes were kept to a minimum while much of the history of each of these large, impressive rock blocks was preserved."

Other recent designs for playground and play scapes include a playground in Amsterdam with minimalist animal sculptures by toy designer Luca Boscardin, and a playground in New York that features repurposed concrete wave breakers painted sky blue.