YELLOWSTONE NATIONAL PARK, Wyo. — The South Entrance to Yellowstone National Park is expected to remain closed this weekend because of a wildfire in Grand Teton where firefighters are trying to clean up hotspots and burned trees along a 2-mile stretch of highway.

The closure of U.S. 89/191/287 that leads into Yellowstone is forcing some park visitors to take an hour-long detour.

Grand Teton fire spokesman David Eaker (A-ker) said Saturday that firefighters are focusing on the highway. They plan to go into wilderness areas off the highway where there are no roads once they get the road reopened, he said.

“They’re trying to button down the areas where values are at risk,” including buildings, campgrounds and other places that have a lot of visitors, Eaker said.

“We want to make sure when the public is allowed back that there are no snags or hotspots,” he said.

Snags include burned trees that can fall without warning, causing serious injury or death.

Firefighters said Saturday that the fire that was started by lightning on July 25 has scarred nearly 20 square miles and continues to spread. Several other fires burning in Yellowstone could require that visitors in vehicles be escorted.

Grand Teton and Yellowstone National Parks and Bridger Teton National Forest all have area closures in effect, but both national parks are open to visitors.

With the highway blocked, visitors in Grand Teton who want to go to neighboring Yellowstone have to drive west into Idaho to access the West Entrance of Yellowstone.