For millions of years, a natural stone arch stretched over a part of Rock Creek Bay in Glen Canyon National Recreation Area ...

The collapse of a popular arch formation on Lake Powell may well have been due to the 190-million-year-old sandstone being submerged by the 61-year-old manmade lake, two experts say. Another ...

The arch was formed from 190 million-year-old Navajo sandstone originating in the late Triassic to early Jurassic periods. The fine-grained sandstone has endured erosion from weather, wind and ...

which was formed from 190 million-year-old Navajo sandstone, the National Park Service said. By Orlando Mayorquín A popular double arch that hung over the turquoise waters of Lake Powell in Utah ...