Four days alone in Yellowstone National Park with the cameras . . . it was early April, and the park remained closed for the winter as final preparations for the prime season were completed. I had access to 40 miles of two-lane road linking the northwest and northeast entries. In the middle of that stretch is Lamar Valley. It has been called the "Serengeti" of North America—appropriately so. ​I hope you enjoy the views of this very special place.