The Louvre Museum in Paris, where the famous Mona Lisa painting is kept, closed suddenly on Monday. The staff went on strike because there were too many visitors and not enough workers.
The workers, including ticket sellers and security guards, said the crowds made their jobs very hard. After four hours of talks with managers, the museum opened again.
Many tourists were upset because they had tickets but got no information about the closure. One visitor joked, 'Even the Mona Lisa needs a break.'
Earlier this year, the French president said the Louvre will get a new area just for the Mona Lisa. This is part of a big renovation project that will take 10 years. Ticket prices will also go up for tourists from outside Europe.
Last year, 8.7 million people visited the Louvre. The museum was built for only 4 million visitors a year. The large crowds cause problems like long lines and not enough bathrooms.
The museum's director has limited daily visitors to 30,000. She also warned that some parts of the building are old and could damage the art inside.