COLUMBIA GORGE, Ore. -- A wildfire is burning on a hillside near Oneonta Falls in the Columbia River Gorge.

Authorities have closed the Historic Columbia River Highway in the area, from Multnomah Falls to Ainsworth State Park. They say the highway is likely to stay closed through Thursday, due to falling rocks from a cliff above the highway, where the fire is located.

The fire is not accessible by trail.

Because of the dangerous terrain, the U.S. Forest Service monitored the fire overnight, and began to attack it on the ground and in the air by daylight Wednesday.

Crews planned to use helicopter bucket drops of water to douse the fire.

About half an acre had burned by Wednesday morning.

No homes are at risk from the fire, but U.S Forest Service authorities advised hikers to stay out of the area, which includes trails to Horsetail and Oneonta Falls.

Gorge Visitors seemed understanding of the situation.

"I still get to see the (Multnomah) falls which is great but I’m not really sure what hikes we’d be missing out on, so we’re making the best of it for sure", said Rachel Brown, who was visiting from out of state with her father.