It has welcomed marathon runners, rock stars and the first modern Olympic athletes. Now its time for a monumental scrub.Athens U-shaped Panathenaic Stadium made entirely of white marble is getting its first systematic cleaning in more than a century.Rebuilt for the first modern Olympics in 1896, the site is the ceremonial send-off point for the Olympic flame, including for Los Angeles 2028.A fresh look in Athens ahead of LA 2028The stadium is made of the same glittering marble used on the Acropolis, making the cleanup job delicate.The work is revealing a monument changed by time, weather and millions of visitors. Cleaners in white and blue overalls move across the stadiums 47 steep tiers with thin spray lances, using clean water at carefully controlled, low pressure. Machines vacuum up the runoff as they go.The goal of cleaning is not to make everything white. Its to remove the dirt and the first layers of organic material that are deposited on the surface, said Dimitris Selemis, a senior conservator at the site.The idea is to clean all the material that (contains) dirt from the surface, so we have a better understanding of the monument, he said, noting that there is more weed growth and dirt in areas that receive less direct sunlight.Dealing with chewing gum, high heels and soft-drink stainsCrews are also using steam to remove blotches of chewing gum, which have turned black over time. Stadium officials say chewing gum, high heels and soft-drink stains are among the main culprits that stain the marble.Now slowly being revealed, the original gleaming look of the venue earned it the widely used Greek nickname Kallimarmaro, or beautiful marble.We call it Kallimarmaro because it is made of the finest marble, the best that was ever produced ... We are very proud of it, Isidoros Kouvelos, president of the Hellenic Olympic Committee, told The Associated Press in an interview.It needed to be cleaned of everything that has accumulated over all these years, he said. This way the Panathenaic Stadium will show all its brilliance and will once again be the foremost monument of humanity for the Olympic Movement.Built into a natural ravine, the stadiums site was used for ancient Greek athletic contests and later Roman spectacles before falling into centuries of disuse.An African celebration planned in AthensSince its 1896 revival, it has staged fashion shows, rock concerts, boxing matches and national celebrations as well as lavish patriotic ceremonies ordered by a military dictatorship in the 1960s.Today, its a popular draw for tourists. Apart from the cleanup, the Kallimarmaro is also getting a new track, upgraded lighting and fresh support facilities. The project is privately funded by a shipping company and overseen by the Hellenic Olympic Committee with guidance from Culture Ministry experts.The work will continue through 2026 but is currently concentrated on the stadiums sling, or curved end, in time for the next torch-passing ceremony on Sept. 10.That will be for the Dakar Youth Olympics, scheduled for Oct. 31-Nov. 13 in Senegal, which will be the first Olympic competition ever hosted in Africa.IOC President Kirsty Coventry, a swimming gold medal winner from Zimbabwe, is due to attend the Sept. 10 ceremony, Kouvelos said.2028 Los Angeles Olympics: Potential breakout U.S. star athletesThe Los Angeles Olympics, with a record 353 medal events, open July 14, 2028. Nick Zaccardi,