Ancient Maps

 According to American history:

Near Kitty Hawk, North Carolina, Orville and Wilbur Wright made the first successful flight in history of a self-propelled, heavier-than-air aircraft on December 17, 1903. Orville piloted the gasoline-powered, propeller-driven biplane, which stayed aloft for 12 seconds and covered 120 feet on its inaugural flight.

Ancient Maps- 

So, how did the ancient mapmakers know how the earth's areas appeared from above?

You can't get the same effect simply sailing a boat.