• Rainbow over Half Dome

    Yosemite

    National Park California

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  • Road Closures Due to El Portal Fire

    The Big Oak Flat Road between Crane Flat and the El Portal Road is temporarily closed. There is no access to Yosemite Valley via the Big Oak Flat Road or Highway 120. Tioga Road is open and accessible via Big Oak Flat and Tioga Pass Entrances. More »

  • Campground Closures Due to Fire

    Crane Flat, Bridalveil Creek, and Yosemite Creek Campgrounds are temporarily closed. More »

  • Yosemite National Park is Open

    Yosemite Valley, Glacier Point, and Wawona/Mariposa Grove areas are open and accessible via Highways 140 and 41. Tioga Road is not accessible via Highways 140 and 41 due to a fire.

Yosemite National Park to Reopen Mirror Lake Loop Hiking Trail on October 18

New trail through fresh granite boulders
NPS Photo

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News Release Date: October 17, 2012

 Trail Closed in 2009 Due to Large Rockfall

Yosemite National Park will reopen the Mirror Lake Loop hiking trail tomorrow, Thursday, October 18, 2012, at 5:00 p.m. The five mile loop that follows Tenaya Creek around Mirror Lake in Yosemite Valley has been closed since March 28, 2009 due to a large rockfall from Ahwiyah Point near Half Dome.  

Yosemite Trail Crews have constructed a new trail on the edge of the talus slope near Tenaya Creek. Work consisted of removing trees and rock in order to create new trail alignment. Several blasting operations have occurred over the past several weeks in order to remove large pieces of granite from the trail corridor and create new material for retaining walls and trail construction. Trail crews will be present on the trail over the next several days to complete the work.  

Rocks fell approximately 1,800 feet to the floor of Yosemite Valley from Ahwiyah Point, knocking down hundreds of trees and burying hundreds of feet of the trail on the southern portion of the loop. The impact of the rocks hitting the ground generated a magnitude of a 2.4 earthquake. The rockfall was estimated to be approximately 43,000 cubic meters, or 115,000 tons. No injuries or structures were affected by the rockfall. The Ahwiyah Point rockfall is the largest rockfall documented in Yosemite National Park since the Middle Brother rockfall event in 1987.  

Rockfalls are a natural and dynamic geologic process. Due to its steep, glacier-carved cliffs, Yosemite Valley experiences many rockfalls each year. Natural processes like rockfall help to create the beautiful and changing scenery in Yosemite National Park.

Did You Know?

Upper Merced Watershed

The Merced River above Nevada Fall and South Fork Merced River above Wawona, numerous small meadows and adjacent riparian habitats occur. Owing their existence to the river and its annual flooding, these habitats help support eight special status animal species: harlequin ducks, black swifts, bald eagles, osprey, willow flycatchers, yellow warbler, western red bat, and Sierra Nevada mountain beaver.