Mona Lisa: That international woman of mystery

Eighty percent of visitors to the Louvre museum in Paris say their objective is to see the "Mona Lisa" painting. No one knows why she smiles or for certain who she is, though she is generally thought to be a Florentine noblewoman.

Leonardo da Vinci worked on the painting from 1503 to 1506 but never considered it finished. He took it with him to France where he lived at the end of his life at the behest of King Francis I, in whose arms he is said to have died.

The "Mona Lisa" was stolen by a Louvre workman in 1911 who wanted to return her to Italy; it took museum officials 24 hours to realize she was gone and almost three years to get her back.

Mona Lisa has loomed large for other artists.

Artist Pablo Picasso and poet Guillaume Apollinaire were briefly suspected of stealing the painting as a prank to promote modern art.

Raphael, Ingres, Delacroix and Corot were inspired by the "Mona Lisa." Marcel Duchamp painted her with a mustache. She traveled to the U.S. in 1963 and to Tokyo and Moscow in 1974, but is not expected to leave the Louvre again.

Last year, the painting was encased in a new climate-controlled, bullet- and UV-proof display at the center of the redesigned Salle des Etats, a $6.2-million project underwritten by Nippon Television.