The National Park Service has closed a 1,000-foot section of the John Muir Trail in Yosemite National Park until further notice after a rockfall sent boulders and trees onto it.
The large rockfall occurred on April 15, obstructing the trail between Clark Point and the top of Nevada Fall, a 600-foot high waterfall on the Merced River in the park.
The trail will require significant repair, including drilling and blasting of large boulders, according to park officials.
Geologists were assessing the potential for more rockfalls in the area.
The John Muir Trail was already closed for the winter season at the time of the rockfall, but will now be closed for at least several more weeks, the park service reported. The gates are closed across the trail at Clark Point and near the top of Nevada Fall.
John Muir Trail was named after naturalist and conservationist John Muir, whose writings and advocacy for preserving western forests were largely responsible for the creation of Yosemite National Park in 1890.
The trail attracts an estimated 1,500 hikers per year, with some completing the trek from Yosemite Valley to the top of Mount Whitney, the highest mountain in the U.S.
About 27 miles of the John Muir Trail is contained in Yosemite National Park.
The National Park Service at Yosemite was not available for comment Friday.