Old Faithful Geyser, Yellowstone National Park, Wyoming.  Icon of our National Parks, Old Faithful erupts 50,000 kilograms of boiling water every 40 to 80 minutes.  Especially beautiful in winter, when few people and no cars are in the park, the geyser’s timetable is not affected by the extreme cold weather.                     
                                                                    Photo copyright R.W. Decker, 1974