Reserva de la Biosfera Barranca de Metztitlán

The Barranca de Metztitlán is a steep canyon cut by the Metztitlán River through the Sierra Madre Oriental, with walls that drop 500 to 700 meters in places. Metztitlán itself sits on the canyon floor, on the green, flat vega where the river spreads out and farmers grow crops between the cliffs. In 2000 about 96,000 hectares around it were declared a biosphere reserve, and in 2006 it joined UNESCO's world network of biosphere reserves.

The reserve is considered one of the most important places for cacti in Mexico. Its dry slopes are covered with columnar cacti, barrel cacti and the shaggy white old-man cactus (viejito), alongside mesquite, agaves and ocotillo, and it shelters more than 270 bird species. To the north, the river ends in the Laguna de Metztitlán, a Ramsar wetland where pelicans spend the winter.

People have lived in the canyon for a long time. The Augustinians built convents here in the 1500s, there are rock paintings on some of the slopes, and the valley is still farmed much as it was centuries ago. It is good country for hiking, birdwatching, mountain biking and simply driving slowly along the canyon road.