The Most Interesting Pieces of Street Art From All Over the World

The More You Know

• Mysterious sand dune holes baffled Indiana for years.
• Only two national flags have the color purple on them.
• A German and British aeroplane shot each other down in Norway during WWII. The crew met and helped each other survive. Two of them later visited each other many years after the war was over as friends.
• The world's largest Barbie collection includes more than 15,000 dolls.