Officina 82 Buries a Corten Steel Marmot Den at 2,173 Meters

At 2,173 meters above sea level, Italian practice Officina 82 has buried a children's learning space inside three Corten steel tubes — with no concrete foundations at all.

The project, called Tana delle Marmotte (Marmot Den), sits at the Pavillon intermediate station of the Skyway Monte Bianco cableway in Italy's Aosta Valley. It's a permanent underground educational installation built for children and teenagers, and its logic is straightforward: take the subterranean habitat of the Alpine marmot and translate it into modular architecture that disappears into the mountainside.

How do you build reversibly at altitude?

The structural shell consists of three prefabricated Corten steel conduits: one central tube 8 meters long, plus two transverse access pipes measuring 2,200 mm and 1,300 mm in diameter. That's roughly the width of a subway tunnel at the widest point.

Instead of pouring concrete, the team set the entire structure on a bed of fine gravel. The tubes were manufactured off-site with flanged connections, weight-calibrated for helicopter delivery, then dry-assembled on the mountain. The approach cuts construction time and eliminates the extended building footprint that conventional work at altitude would demand — and it means the whole intervention can theoretically be unbolted and removed.

What does the interior look like?

Inside, the fit-out takes its cue from the winter hibernation tunnels marmots dig. The lining uses 40 mm thick, three-ply spruce plywood ribs anchored to perimeter timber rings that mirror the circular steel profile. Infilled with tongue-and-groove spruce boarding, the contoured ribs form one continuous, fluid spatial volume.

The timber isn't just cladding. It works as ergonomic seating, display cases, graphics mounts, and a carved staircase leading to a transparent acrylic porthole where visitors can look out over the surrounding terrain — the same porthole doubles as a skylight, pulling natural light into the buried interior. Overhead LED strips trace the curved ceiling profile to guide visitors along the educational route.

Recyclable materials — steel, Corten, and timber — were specified throughout.

Who built it?

Officina 82's lead designers were Fabio Revetria and Lara Sappa, with collaborators Arianna Garelli, Lucrezia Nari, and Simone Bianchi. The team included structural engineer Corrado Curti of IngeMBP, geologist Paolo Zamparutti, metalwork by Nuova Sicmi, interior design by Studio Arredi, MEP engineering by CED Impianti Group, permits handled by IdeaLAB, and general coordination by Giulia Sarno, who also photographed the project. The client is Skyway Monte Bianco.

The project models a direction alpine construction is likely to keep pushing: fully prefabricated, dry-assembled, and reversible buildings that leave the high-altitude ecosystem essentially untouched when the client eventually wants the mountain back.