Gilbert H. Grosvenor, National Geographic magazine’s founding editor, is credited with saying: A map is the greatest of all epic poems. Its lines and colors show the realization of great dreams.

This story appears in the April 2010 issue of National Geographic magazine. On a blistering day in the megalopolis that is southern California ... a finger across a map of some 60,000 acres ...

8 min read This story appears in the September 2013 issue of National Geographic magazine. The maps here show the world ... Florida and the Gulf Coast. In California, San Francisco's hills would ...