Yellowstone National Park’s famous geothermal pool named Morning Glory has reportedly changed color due to the volume of debris thrown in by visitors. According to park historians and former ...

“It’s one way that values and behavior have changed over the years.” Yellowstone tourists blamed for ruining pristine color of park’s ‘Morning Glory’ thermal pool: ‘Thousands of coins’ ...

He can’t imagine the Park Service doing something similar now, however, given the difficulty of the work. “Cleaning pools was done on a regular basis,” he said.