Look for landmarks from the plane
Look for landmarks. If a river is so big that its width is discernible from 30,000 feet, the chances are good that you’ve heard of it. Shorelines are easy to decipher. Flights between Berlin and Stockholm, for instance, pass over a large and very striking lagoon on the coast of the Baltic Sea. This is Szczecin Bay, at the mouth of the Oder River on the Polish-German border.