Villa Troglodyte has been built inside a rock in Monaco (Credit: Photo: Loïc Thebaud)

To say that space is tight in the Principality of Monaco is an understatement. The pint-sized country, which has a surface area of just 0.78 square miles (2.02 square kilometers), boasts a total population density of 48,466 people per square mile — the highest in the world. With building space stretched to the limit, architects in the world's second-smallest country have been constructing up towards the sky, tunneling down into the ground, and even carving out the surrounding cliffs. Now, they have built a multi-million dollar luxury home inside a rock.

The swimming pool etched inside the bedrock represents an underground lake (Credit: Loïc Thebaud)

Located along Monaco's bustling Hector Otto Avenue, Villa Troglodyte (French for "living in a cave") is the brainchild of architects Jean-Pierre Lott and Patrick Raymond. Completed in August 2019, the five-level, three-bedroom luxury home boasts 5,381 square feet (500 square meters) of living space. Though that is large by any standard, it is palatial in Monaco, where homes as small as 1,152 square feet (107 square meters) are considered a "good size."

Villa Troglodyte has three bedrooms, each with a built-in-balcony (Credit: Loïc Thebaud)

Visitors are greeted by a gorgeous swimming pool — a metaphor for an underground lake — with a small footbridge to get to the adjoining hall. Alongside lies a garage, complete with an electric-charging station. The living room and three bedrooms are located on the upper floors and can be accessed by a staircase or a glass elevator.

Natural light filters in through a large rock fracture that runs through the entire house. All the living areas have also been strategically carved to receive an optimal amount of sunlight. Though some of the upper rock planes had to be removed to add the extra floors, the exterior was refinished to mimic the original surface, complete with vegetation, cracks, and cavities. As a result, the luxury home blends in perfectly with the surrounding Monaco landscape.

Villa Troglodyte has been built to take advantage of the natural light (Credit: Loïc Thebaud)

“Contrary to traditional houses... where you erect walls and build floors, where you work by adding elements, here we’re digging into the ground, looking for spaces, sculpting the material,” said Lott. “In that respect, it’s the opposite way of working.”

Villa Troglodyte minimizes its environmental impact with numerous "green" elements. The structure is constructed using low carbon concrete and insulated with cork. The floors are made using recycled wood, while the doors and staircases are crafted from material obtained from responsibly and sustainably managed forests. The house is powered by solar panel arrays fitted on the roof. The architects assert that thanks to the various features, the luxury home uses less than 40 percent of the energy of a typical European home.

Villa Troglodyte features numerous eco-friendly features (Credit: Loïc Thebaud)

As you may have guessed, a house this unique, especially in Monaco where all real estate sells for a premium, does not come cheap! Though there is no official listing yet, experts estimate the work of "art" to sell for between $33-$44 million (30 to 40 million euros). Gives a whole new meaning to living under a rock, doesn't it?

Resources: NewAtlas.com, www.world-architects.com, www.reuters.com