Contained within the apparent peacefulness of the scene is a lurking threat. The nearby Popocatépetl volcano is stirring after more than half a century of quiet and could someday erupt on a scale not seen for a thousand years. Tens of thousands of people in a 660-square-mile area might have to flee for their lives, and public and private resources to carry out such an evacuation are slim.

(Text adapted from and photograph shot on assignment for, but not published in, "Popocatépetl: Mexico’s Smoking Mountain," January 1999, National Geographic magazine)