In the Grand Canyon of the Yellowstone River, Lower Falls is Yellowstone National Park's highest waterfall.
The green color of the water that extends part way down the falls is caused by a notch in the riverbed at the top of the falls.
It allows the river to reveal some of its natural color instead of immediately breaking into spray.
During the spring months, the amount of water flowing over the falls is estimated at 65,000 gallons per second.
A short but steep trail from the North Rim takes visitors to the brink.