What is most well known piece?

The most well-known piece of art in the world is likely the Mona Lisa, a painting by Leonardo da Vinci completed between 1503 and 1519. The Mona Lisa is a half-length portrait of a woman, believed to be Lisa del Giocondo, wife of Francesco del Giocondo. The painting is considered to be a masterpiece of the Italian Renaissance and is one of the most visited and famous works of art in the world. It is currently housed at the Louvre Museum in Paris.