WHEN I FIRST HEARD ABOUT EL CIELO, the forest in the mists, I thought it must be a mythical place. I could hardly imagine a cool, verdant cloud forest, with ferns, orchids, macaws, and lofty alpine meadows, all within a day’s drive of the Texas border in the dusty state of Tamaulipas. Although it was named a biosphere reserve by the United Nations back in 1985, El Cielo (which means “the sky” or “heaven”) has remained something of a secret, hidden high within the eastern folds of the Sierra Madres. Clouds drifting inland from the Gulf of Mexico, trapped by the mountains, linger and drop more than 120 inches of rain a year on the forest, creating a treasure trove of biodiversity—a rare crossroads where a jumble of flora and fauna from north and south come together in startling proximity.
El Cielo has been protected, in part, by its remoteness. It lies less than three hundred miles south of the border, but it feels as mysterious and otherworldly as