The tan-colored Navajo sandstone produces some notable arches in Zion National Park, but not as many as is produced by the salmon-colored Entrada sandstone farther east in Arches National Park.
Still, Zion can boast of one of the biggest, if not the biggest arch — the Kolob Arch, measuring 287 feet. Landscape Arch in Arches is considered to be slightly longer at 290. The longest arch in the world in Fairy Bridge in Guangxi, China at 295 feet.
As water percolates through sandstone, said Michael Plyler, director of Zion Field Institute, the glue that binds all those grains of sand is weakened. The forces of water and gravity cause rock falls up farther up in the rock formation, he said.
“The legs of a formation have a pretty solid foundation,” said Plyler. “Look at how a keystone in a bridge distributes weight down the legs.”
Other natural arches that can be seen in Zion include Crawford Arch, as well as Pico Rosado Arch, Two Pines Arch, Checkerboard Arch, Hidden Canyon Arch and Jug Handle Arch.
Those who explore the slot canyons of Zion can find off-the-beaten-track arches such as Eye of the Needle, Heaps Canyon, Imlay Canyon, Englestead Hollow, Pine Creek Canyon, Spry Canyon, Fat Man’s Misery and The Subway. And way off in the remote backcountry, there’s Hammerhead Arch and Elephant Arch.
There’s also something geologists call a “blind arch.” These are where huge slabs of sandstone have broken away from the side of a cliff, leaving the shape of an arch.
