The Rio Grande offers an environment that is totally different from the surrounding desert. We experienced the river at the southwest and southeast corners of the park.

At the Santa Elena Canyon Overlook we could see the point at which the Rio Grande breaks through the 1,500-foot cliffs of the Sierra Ponce.

From a distance it seems unlikely that the Rio Grande could make its way through such a narrow canyon. The river valley supports a much denser layer of vegetation.

The trail up the canyon passes through vegetation more suited for the environment along the river.

At this point the Santa Elena Canyon narrows and the trail ends. In this photo, Texas is to the right and the Mexican state of Chihuahua is to the left.

Here the Rio Grande cuts through the Sierra Del Carmen.

From the Boquillas Canyon Overlook, the route of the river through the mountains is impossible to see.

We had fleeting glimpses of roadrunners throughout our visit. This one in the Rio Grande Village parking lot stopped long enough for us to get a better look.

We learned that in the southwest, the greater roadrunner is known by the Spanish name of "Paisano," or countryman. The roadrunner is used as a logo throughout the park.

At Rio Grande Village we also spotted a band of collared peccaries—or javelinas. We later saw them in various places throughout the park.

Javelinas are related to pigs, although they are classified in a family of their own due to anatomical differences.