Yosemite's New Danger: Plunging Boulders

It used to be that you had to watch out for bears, forest fires, or even waterfalls at Yosemite, but there's a new danger at the iconic national park: Falling boulders are now closing swaths of some popular haunts for good. The National Park Service will today announce that potential danger from the unstable 3,000-foot-tall Glacier Point, a granite promontory that for decades has provided a dramatic backdrop to park events, will leave some of the valley's most popular lodging areas permanently uninhabitable.

"There are no absolutely safe areas in Yosemite Valley," says Yosemite's staff geologist and author of a new study that assesses risk from falling rocks in the steep-sided valley. The highest risk area is family friendly Curry Village, which was hit by a major rock fall several years ago. A newly delineated "hazard zone" also outlines other areas, including the popular El Capitan, where danger posed by the rock falls is high but risk of injury is low because they aren't continuously occupied. An AP examination after a 2008 fall found park officials were aware of USGS studies dating back to 1996 that show Glacier Point behind Curry Village was susceptible to rock avalanches. Yet visitors were not warned, and the park service repaired and reused rock-battered cabins. Last year 53 rock falls occurred. (More Yosemite National Park stories.)