The glass pyramid that I. M. Pei placed in the Napoleon Courtyard of the Louvre in Paris is a structural answer to how a contemporary structure can be added to a historic context: by being as nearly invisible as possible.

Pei's design problem was to build the museum's new main entrance without overwhelming the Baroque palace around it. His solution was to design the most transparent structure possible. The 21.6-metre pyramid is made of 70 triangular and 603 rhombic glass panels. The structure holding this glass is made as slender as it can be: a net of thin stainless-steel rods and tensioned cables holds the glass from within by tension. Instead of thick load-bearing columns, slender elements tensioned like the rigging of a sailing ship are used; the structure thus nearly disappears, leaving only the glass surface.

The pyramid is also a lighting device that carries daylight down into the new underground reception hall; visitors disperse from beneath this glass cone into the wings of the palace. Rather than adding a monumental mass, Pei unites the new with the old without conflict by building a light-transmitting transparent geometry. The Louvre Pyramid thus turns contemporary glass-and-steel tension engineering into a minimal architectural intervention respectful of a historic setting.