One of the most dramatic images shows the entire Manhattan skyline, a dense slab of glass and steel, laid across the high ...

View from the mouth of Santa Elena Canyon, Big Bend National Park, Texas. View from the mouth of Santa Elena Canyon, Big Bend National Park, Texas. Tim Speer/Getty Images In Southwest Texas along ...

Mud slurps at my shoes as I slog along the banks of the Rio Grande, deep in the heart of Santa Elena Canyon at Big Bend National Park. In front of me, Charlie Gandy, founder of the Cross Texas ...