Window Trail Stop #7

Casa Grande captures the last sun of the day

NPS/W. Tesarek

Quick Facts

Location:

Big Bend National Park

At first glance, the Chisos Basin appears to be the remains of a large volcanic crater. And while the mountain peaks forming the rim of the Basin are of igneous origin, there apparently was no volcano in the Basin. Current theories regarding the creation of the Chisos Mountains say that beginning about 38 million years ago, two volcanoes to the south and east of what are now the Chisos Mountains spewed ash and lava to the surface, while a non-erupting source squeezed molton rock into the bedrock from below. After eons of erosion, the resistant rhyolite magma intrusions remain as the mountains surrounding the Window. Turn around and take a look at the tall, square mountain dominating your view. That mountain is named Casa Grande, which is Spanish for Big House. Many visitors think Casa Grande is the highest peak in the park, but that honor is reserved for Emory Peak, located further to the right. At 7,832 feet, Emory Peak is the third highest mountain in the state of Texas. It was named for Major William Emory, head of the United States-Mexican Boundary Commission, which established the Rio Grande as the boundary line between the United States and Mexico.