A mountain full of Petroglyphs. Notice the lizard in the center. September 14, 2012 by Matt ThomasA mountain full of Petroglyphs. Notice the lizard in the center. Dinosaur National Monument About Matt Thomas Matt is an avid writer and explorer, who loves to showcase his home state of Colorado. His favorite place to be is right here in the Centennial State. Previous Post:A mountain full of Petroglyphs. Notice the lizard in the center.