Early maps often charted constellations. They were painted onto cave walls or carved into stone. As people began to travel and explore more of the world, geographical maps started to come together.

Once this photolettering process was refined, it was applied to our United States map supplement in the May 1933 National Geographic. Shortly thereafter, Society cartographer Charles E.

8 min read This story appears in the September 2013 issue of National Geographic magazine. The maps here show the world as it is now, with only one difference: All the ice on land has melted and ...