No one really know who Mona Lisa was, who commissioned the portrait, how long Leonardo da Vinci worked on it, how long he kept it, or how it even came to be in the French royal collection. However, the Mona Lisa painting is easily the most famous, most studied, and the most widely recognized painting in the world. Take a look below for 25 more interesting and bizarre facts about the Mona Lisa painting.

1. The Mona Lisa was painted using oil paint on a poplar wood panel, using a technique that left no visible brush marks.

2. Her smile, which is famous for its intriguing nature, is an enigmatic aspect of the historic portrait.

3. The dimensions of the painting are 53 by 77 centimeters, or 21 by 30 inches. This makes it just a little bit bigger than an A2 piece of paper.

4. The title of the painting, “Mona Lisa”, means “My Lady Lisa”, in Old English.

5. The painting is now over 500 years old.

6. Modern face recognition software has found that Mona Lisa is 83% happy, 9% disgusted, 6% fearful and 2% angry in the portrait.

7. It’s currently located at the Musee du Louvre in Paris, France, where it has a room of its own. It’s been on permanent display since 1797.

8. Over 6 million people visit the painting at the Louvre each year. An average person spends 15 seconds looking at her.

9. The painting became even more famous when it was stolen from the Louvre in 1911.

10. While the painting was missing, 6 wealthy Americans were tricked into paying up to $300,000 each for fake Mona Lisa paintings.

11. Pablo Picasso was once a suspect in the theft of the famous painting, and was even brought in for questioning.

12. The Mona Lisa is considered to be priceless, which is why it can’t be insured.

13. Many people believe that the painting was created in the image of Lisa Gherardini, but others believe that it’s actually a self portrait of Leonardo da Vinci himself.

14. Mona Lisa’s eyebrows and eyelashes are missing, but the reason why has been debated over the years. Some believe that they were accidentally removed during a restoration. Others believe that they’re missing because of Leonardo da Vinci’s obsession with perfection in his work, which resulted in him never completing the painting. It was also popular at the time of the painting’s creation for women to completely pluck their eyebrows and eyelashes, so Mona Lisa might not have had any to begin with.

15. There are 3 previous layers beneath the Mona Lisa that depict her in different poses.

16. In 1913, Vincenzo Perugia was found to have stolen the Mona Lisa from the Louvre. He was an Italian patriot and believe that the painting should be in Italy. He was also an employee at the Louvre when he stole it and he kept it in his apartment for 2 years. He was found when he tried to sell it to a gallery in Florence, Italy.

17. The Mona Lisa has its own climate controlled room in the Louvre Museum in Paris, with bullet proof glass to protect it. The room has been estimated to have cost more than $7 million to build.

18. In 1956, before the painting had its own room, Ugo Ungaza threw a stone at the Mona Lisa and damaged a portion of the painting near her left elbow.

19. There’s a second Mona Lisa painting in Museo del Prado, Madrid. This painting is thought to have been painted by one of Leonardo da Vinci’s pupils. When it’s viewed with the original Mona Lisa, it created a 3D effect, making it the first stereoscopic image in history.

20. When painting the Mona Lisa, Leonardo da Vinci had six musicians play for her and installed a musical fountain he invited himself. He did all this because he wanted to keep his subject relaxed and entertained.

21. Leonardo da Vinci invented scissors, played the viola, and spent 12 years painting the Mona Lisa’s lips.

22. During World War II, the Mona Lisa was moved 6 times so it can be kept out of the hands of the Nazis.

23. In 1983, a Japanese artist called Tadahiko Ogawa, made a copy of the Mona Lisa completely out of toast.

24. The painting was loaned to the National Gallery for a month in 1963. Its visit included 24 hour security by U.S. Marines and even with expanded viewing hours, the line to wait was often 2 hours long.

25. The French emperor, Napoleon Bonaparte, once had the Mona Lisa hanging in his bedroom, where it was said that he reveled in her beauty for many hours.