In the late 1990s, Ole Barslund Nielsen “basically didn’t have a career,” he says. Trained as a sculptor, he was taking whatever odd jobs he could find, mostly building sets in Copenhagen theaters. He met Christian Jensen, a furniture designer, on a freelance assignment setting up a design exhibition and quickly realized he had found a kindred spirit: Creatively, both men had hit a wall. “We had no responsibility at all,” Jensen says.

The two started brainstorming possible collaborations. They came up with many bad ones, including an organization that would run team-building exercises for adults, like rafting trips, “something that we wouldn’t know anything about,” Nielsen says.

They might have pursued one of these doomed ideas had a more fruitful possibility not presented itself. Nielsen had volunteered to help choose a new playground for his son’s kindergarten class. He realized that, for the budget allotted, he could build something like a theater set. He designed a three-story pink “Princess Tower” connected to a massive rocket and then merged the two structures with classic playground elements: a ladder, two bridges and a slide.