Over many millennia, on its way to union with the Missouri River in westernmost North Dakota, the Yellowstone River has carved its way into the volcanic plateau to form Grand Canyon of the Yellowstone. This gorge is about 1/5 the depth of the Arizona Grand Canyon. Lower Falls ranks as highest of the two at 308 feet, and the largest waterfall in the Rocky Mountains, spilling over hard ledge of 590,000-year-old rhyolite from the latest major eruption sequence. Thanks to being in a national park, this powerful and humbling scene still appears much as painted by Thomas Moran, looking from two places within a mile downstream from my spot, in 1872 and 1901, and photographed by Ansel Adams in 1941, from a ledge roughly in the middle of this shot.
