Virgin River-Zion National Park
The Virgin River and its tributaries run through Zion National Park. This water is the primary agent of erosion that continues to carve and shape Zion.
The North Fork of the Virgin River begins north of Zion at Cascade Falls, where it drains out of Navajo Lake at 9,000 feet above sea level. The East Fork of the Virgin River originates above Long Valley. Both the North and East Forks of the Virgin River run through the park and empty into Lake Mead at about 1000 feet above sea level, where it joins the Colorado River.
Though the Virgin River is relatively small, it is incredibly steep. The river drops roughly 7,800 feet in the 160 miles it travels. In the park, the river drops an average of 71 feet every mile. In comparison, the Mississippi River drops about one inch every mile. This steepness, caused by the uplift of the Colorado Plateau, has given the Virgin River the ability to cut through sandstone and carve canyons.