Whether it’s your first time visiting, or you’ve explored Big Bend too many times to count, driving to Rio Grande Village to view the Sierra Del Carmen range is always a highlight. The Sierra Del Carmen feature layers of limestone formed from thick muds containing the remains of sea-dwelling animals left behind by an ocean that once covered the area. Like the Chisos Mountains found within Big Beng National Park, the Sierra Del Carmen in Mexico is a “sky island in a desert ocean.” While only ten square miles of the Chisos Mountains lie above 5,500 ft., over 100 square miles of the Maderas del Carmen lie above that elevation. Animal life, like the plant life, topography, and geology, is similar on both sides of the border, although the Mexican black bear and certain other mammals are present in greater numbers in Mexico. Today, on International Mountain Day, we celebrate the learning opportunities provided by the relationship between these similar sky islands and all mountain ranges around the world. To learn more about mountain ranges found in National Park sites, visit https://www.nps.gov/subjects/mountains What mountain range holds a special place in your heart? 📷: NPS/D. Wellborn #bigbend #bigbendnationalpark #internationalmountainday #sierradelcarmen