This story appears in the November 2013 issue of National Geographic magazine ... and William Clark on their epic journey across North America. The other one is just beginning.

North America is the third largest continent in the world. It is located in the Northern Hemisphere. The north of the continent is within the Arctic Circle and the Tropic of Cancer passes through ...

On a map, that put North America's geographical center 6 miles west of a town called Balta, North Dakota, which is itself 16 miles southwest of a town named Rugby. Rugby was quick to claim the ...