Wrigley's Spearmint Gum Ghost Sign

from flickr user rubey-kay
Before billboards, companies would make use of the sides of buildings -- most often brick buildings -- to advertise their products. This ghost sign for Wrigley's Spearmint Gum is still somewhat visible on the side of a downtown Mankato, Minnesota (home of the Minnesota Vikings training camp) business. I believe it is located on Mankato's Riverfront Drive and I'm fairly certain I saw it on our way to Chipotle during our trek home from a friend's cabin.