Authorities say a wildfire is threatening several hundred homes near the main entrance road to Yosemite National Park. Cheryl Goetz, a spokeswoman for the California Department of Forestry and Fire Protection, says the 1,000-acre fire is burning in steep, rugged terrain along both sides of the Merced River. The Mariposa Sheriff's Department is warning residents of the town of Midpines to prepare to evacuate. Midpines is located along Highway 140, the thoroughfare to the west entrance of Yosemite National Park. Campers on nearby Bureau of Land Management land were evacuated as a precaution. Fire crews were being flown Saturday into the hard-to-reach area. The fire was first reported Friday.