Boulder Park: 3D-Printed Concrete Caves for Play

XISUI Design didn’t treat “playground” as a fenced-in object dropped into a park. In Boulder Park, Jinan, the studio builds the whole experience around boulders and a surprisingly convincing man-made “canyon” made with 3D-printed concrete. The result is less about a single headline installation and more about a sequence of places where climbing, splashing, resting, and wandering feel like one continuous landscape.

Set within Yunwan Garden at Vanke Snow Mountain City, the 13,000 sqm community park reads like a small ecology of play: sand, creek, shade, and stone. Instead of separating kids from everything else, the design folds children’s activity zones into the same spatial language as the wider site, so parents and grandparents aren’t just supervising from the sidelines. :contentReference[oaicite:0]{index=0}

From “Play Equipment” to Play Terrain

The All-Age Boulder Playground leans on a simple move: treat natural stone as structure, furniture, and prompt. Boulder clusters hover over sand pits as climbing and lounging elements, while smaller stones and edges become informal steps and perches. That kind of ambiguity is the point. Kids do not need instructions when the ground itself suggests what to do next.

More conventional play items still appear, but they are absorbed into the setting. Swings, tunnels, ropes, and rotating pieces are placed so they feel embedded, not applied. The composition keeps sightlines open, making it easy for adults to stay connected without turning the park into a control room.

Water as a Social Connector

West of the main playground, the Water Garden shifts the park into shallow streams, fountains, and hands-on devices that turn water into an experiment. This is not the loud “splash pad” vibe. It is a slower sequence of flow, pressure, and small discoveries, with creeks that bend and pause like they were always there.

That gentler pacing matters in a community park. Water draws different ages into the same zone: kids chase motion, adults hover at the edges, and everyone ends up sharing the same micro-landscape. It is a surprisingly effective recipe for intergenerational use without forced programming.

The 3D-Printed Cave as a New Kind of Playground

The project’s standout move is the cave-like adventure space built with 3D concrete printing. A robotic arm extrudes concrete layer by layer, producing monolithic curved forms that would be painful, expensive, or imprecise with traditional formwork. Here, the layered texture is not a flaw. It becomes the “geology,” visually tying the printed structures back to the boulder theme.

Those subtle ridges and curves do real work: they naturally form steps, seating ledges, handholds, and slide-like surfaces. The park quietly proves that digital fabrication can produce public-space elements that feel less like gadgets and more like terrain.

Safety, Durability, and the Reality of Public Use

Because this is a kids’ environment, the printed installations are shaped with rounded corners and smooth edges, aiming to keep exploration safe without draining it of challenge. The design also acknowledges that landscape structures often have clear functional demands but varied use patterns, which makes them a practical testing ground for new construction methods.

According to the project team, the 3D printing concrete reached an average strength around 50 MPa, positioning it comfortably for landscape-scale structures while prioritizing outdoor durability and reduced reliance on labor-intensive craft. In a public park, the real win is not novelty. It is how reliably the place holds up while staying inviting.

In Boulder Park, XISUI Design uses boulders and printed “canyons” to make a park where play feels like a natural behavior, not an assigned activity. It is a solid argument (literally, concrete) that emerging fabrication tools can support warmer, more intuitive public spaces when they are guided by landscape logic instead of tech spectacle.