Firefighters soak down a smoldering area near an entrance road to Yellowstone National Park. The fire that began last month in neighboring Grand Teton National Park is blocking Yellowstone's south entrance, near Jackson, Wyo.

GRAND TETON NATIONAL PARK, Wyo. — Firefighters chopped down trees and searched for hotspots on steep hillsides Sunday as they battled a wildfire that has blocked an entrance to Yellowstone National Park.

Wildfire managers said their top priority is clearing a highway that leads to Yellowstone and protecting campgrounds, buildings and archaeological sites. They also are making sure there are no flare-ups or falling trees that could cause injuries or death.

Strong winds blew down several trees Saturday, blocking some roadways. Travelers have been warned to be cautious on roads around the park that remain open.

The fire that began last month in neighboring Grand Teton National Park is blocking Yellowstone’s south entrance, near the resort town of Jackson. Yellowstone also has entrance stations near Cody and in Montana.

Joel Dugger, who is with a wildfire crew based near Redding, Calif., said he and six other firefighters have been working for 10 days to corral the Grand Teton fire and keep it contained.

“That way we won’t have a potential re-burn through these areas that are green,” he said, pointing to nearby fir trees on a mountainside that have so far withstood intense heat and embers.

Surrounded by swirling smoke from burning logs that were chopped up with chain saws and axes, Dugger said there have been long days on the fire lines, and firefighters sleep in tents at night.

“We survive in the backcountry. We’re self-sufficient a week at a time,” he said.

Wildfire managers are letting the fire continue to burn on Jackson Lake’s west side, where no buildings or people are threatened.

Linda Burroughs, a visitor from Russell, Pa., who is traveling with a group of senior citizens, said the wildfire cut short their planned two-day visit to Yellowstone National Park. They had to take a four-hour detour to get to their Jackson Lake lodge, south of the Grand Teton fire.

“We see the smoke off and on,” she said, but so far, the fire isn’t threatening tourists at the lodge.