THE HISTORY OF THE BLUE BALL TAVERN & THE PURPOSE OF THE BLUE BALL
During the late 18th & early 19th centuries, innkeepers along a stagecoach route in Delaware, Pennsylvania, and Ohio developed a signal to let illiterate drivers know whether they needed to stop and pick up passengers.
Each innkeeper attached a large ball painted blue to a pole in front of his tavern. If passengers were waiting to board the stagecoach, the innkeeper would raise the ball. Otherwise, the ball would remain lowered, and the stagecoach driver could pass by without stopping.
— From the corner of Rockland Road and Concord Pike, the Blue Ball Tavern served passengers traveling through Delaware, Pennsylvania and Ohio.
— A large pole with a blue ball that could be raised or lowered was located in front of the tavern.