article_snippet: Tunisia's largest museum, built in a 15th Century palace .
article_snippet: Contains 8,000 works, including one of the world's largest collections of Roman mosaics .
article_snippet: Some items in the collection are more than 40,000 years old .
article_snippet: A new wing was added in 2009, doubling A new wing size .
article_snippet: As investigations into the massacre continue, Tunisian security officials have been asked why the world-famous museum was completely unprotected.