When it was unveiled 30 years ago, Chinese-American architect I.M. Pei's glass pyramid at the Louvre Museum was scorned by Parisians.
Now, it has become as iconic as the Paris museum, which is home to famed treasures such as the Mona Lisa.
The pyramid celebrated its 30th birthday last Friday with a huge black-and-white collage by French artist JR in the courtyard where the glass monument stands.
It took four days for some 400 volunteers to paste strips of printed paper on the courtyard's cobblestones, creating an optical illusion of the pyramid plunging into a chasm.
Despite early criticism, Pei's pyramid is now heralded as a French monument. It has been the backdrop for fashion shows, film screenings and political rallies, and is also a popular picture-taking spot.