Grassy meadows, rimmed by the bright green leaves of cottonwood trees, bordered by the turquoise waters of the Virgin River, give way first to steep slopes of tumbled red rock, decked with the dark green of juniper trees and the gray-green of sagebrush, and then to the vertical cliffs of red- and cream-colored sandstone, rising to implausible heights on either side of the canyon, and capped majestic formations reminescent of towers and temples. The Virgin River, originating in the 10,000 foot peaks of the mountains of the Kolob Terrace, has cut its way through as much as two thousand feet of hard sandstone in a gorge (the Narrows of the Virgin) that is as narrow as twenty feet in places. At a point near the Temple of Sinawava, the river reaches a softer underlying layer called the Kaibab Formation, where the canyon begins to widen out. A prehistoric landslide low in the canyon once formed a lake in this section of the canyon, and the dried-out lake-bed provides the fertile and flat floor for meadows and cottonwood trees.
Above Zion's towering cliffs lies a rugged country of slickrock, broken by box canyons and cliffs. Originally this country was a flat mesa, and many flat remnants of this can be found, covered with junipers, surrounded by steep drop-offs of barren rock, ending in the canyons and desert vegetation below. Erosion has played its tricks on the surface of the stone, etching unearthly patterns on wide surfaces, and turning small surfaces into pinnacles and hoodoos.
Miles of hiking trails provide access to the beautiful and popular sights near the road as well as remote and fantastic areas less commonly visited. Zion Canyon's walls are dotted with springs and creeks, seeping out of the towering cliffs, which provide for microclimates of water-loving vegetation, waterfalls and "weeping rocks".
Zion is also home to one of America's longest tunnels. In order to connect the Saint George area to U. S. Highway 89 on the other side of the park, a tunnel over a mile long was constructed through the cliffs of Zion Canyon on State Highway 9 in the 1920s.
Zion Canyon was designated a national park Nov. 19, 1919 and covers 146,592 acres. 2,608,564 people visited the park in 2005.