Depending on where you stand, Grand Staircase–Escalante National Monument has been quietly doing its thing for between 275 million and 50 million years. But it’s relatively new to us humans: It was the last part of the lower 48 United States to get cartographed, and once people started poking around they realized they were dealing with an un-spent wealth of ancient and modern science and culture. President Bill Clinton set it aside as a national monument in 1996 because its untrammeled significance distinguishes it for researchers and explorers alike.