By Laila Kearney
SAN FRANCISCO, Aug 23 (Reuters) - A massive California wildfire raged at the backcountry edge of Yosemite National Park on Friday, threatening one of America's renowned outdoor destinations as it grew overnight and resisted firefighters' efforts to control it, authorities said.
By Friday morning, the wildfire had grown to over 105,000 acres (42,500 hectares) from 64,000 acres on Thursday and had devoured two more homes and a handful more outbuildings as hot, dry air and winds fed the flames.
The so-called Rim Fire, named for a Stanislaus National Forest lookout point called Rim of the World, was the fastest growing of 50 large wildfires burning throughout the U.S. West.
It crossed into Yosemite in a rugged area near Lake Eleanor, a nearly century-old scenic reservoir near the park's western edge, although most of the fire was still burning outside the park, fire information officer Ashley Taylor said.
"Firefighters are still going to have a stressful situation out there," Taylor said of the blaze, which was burning in rugged, remote terrain. "We are just expecting a very active fire."
Only two percent of the fire was contained as of Friday, and firefighters were concentrating on protecting homes and communities.
California Governor Jerry Brown declared a state of emergency on Thursday in Tuolumne County, where the fire is burning. A total of four homes and 12 outbuildings have been destroyed since it broke out on Saturday.
Additional evacuation orders have been given for more homes near the burn zone, and another 2,000 homes were now considered under threat, up from 2,500 on Thursday. Taylor could not say how many people were affected by the orders.
Until now, the evacuation orders have included at least 19 recreational areas in Stanislaus National Forest, among them campgrounds and recreational vehicle campsites. Two evacuation centers have been set up for people displaced by the fire.
The National Park Service said that Highway 120, which leads to the west side of Yosemite, was temporarily closed. It is one of four access routes to the park. The cause of the Rim Fire is under investigation.
Yosemite National Park, famous for its waterfalls, giant sequoia groves and other scenic wonders, covers 750,000 acres (300,000 hectares) and supports a highly diverse animal population.
The park, which is 195 miles from San Francisco and 315 miles from Los Angeles, attracted nearly 4 million visitors last year. http://www.nps.gov/yose/index.htm (Writing by Cynthia Johnston; Editing by Toni Reinhold)