After some exhibitions in Italy, Mona Lisa was again returned to the Louvre. In 1956, an attempt to destroy the Mona Lisa with acid damaged the lower half of the painting. The subsequent restoration took several years. In the 1960's and 1970's, the Mona Lisa want travelling again for the last time, to be displayed in New York, Tokyo, and Moscow. Today the painting is, at long last, at rest, behind bullet-proof glass in the Louvre.
International agreements prohibit any further journey.
But Mona Lisa must have had the highway blues, you can tell by the way she smiles. The Mona Lisa's smile is the most intriguing part of the painting. He wanted it there. Leonardo made a habit of recording all his model sittings in his notebooks. It is therefore very strange that, in no place in any of his notebooks is there a single mention of the Mona Lisa model sitting.