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Santa Elena Canyon is one of the most famous canyons in Big Bend National Park. It separates the limestone mesas of the Mesa de Anguila on the northern or Texas side of the Rio Grande River from the Sierra Ponce on the southern or Mexican side. The canyon was carved out of thick layers of limestone originally deposited as sediments in the shallow sea that covered the Big Bend between 60 million and 130 million years ago.
Image credit: NPS Photo/Mark Schuler
