Utah Geological Survey mapping geologist Grant Willis recently confirmed that Landscape Arch, in Arches National Park, is the world’s longest natural arch.
Landscape Arch and other contenders were measured using a new standardized method developed by the Natural Arch and Bridge Society. Landscape Arch topped the list with its measurement of 290 feet. It beat long-time rival Kolob Arch in Zion National Park (which measured 287 feet) by just three feet.
Previous measurements of Landscape Arch were between 291 feet and 306 feet. Meanwhile, Kolob Arch measurements ranged from 282 feet to 310 feet.
Ranger Kathryn's Arches 