A historic fire lookout in Yellowstone National Park burned to the ground last week after being hit by lightning. A radio repeater was also damaged in the blaze.

The lightning bolt struck the Mount Holmes Fire Lookout during a severe thunderstorm that passed through the area on the afternoon of July 16, Yellowstone officials say.

Built in 1931 and renovated about 20 years ago, the lookout sits about 10,000 feet above sea level, southwest of Mammoth Hot Springs and north of Madison Junction. It had not been used as a staffed fire lookout since 2007.

“The building was eligible for inclusion on the National Register of Historic Places, both for its significance in early park resource protection efforts, and as an outstanding example of the rustic architectural style that typified early park architecture. We are disappointed that this historic structure, as a window into the past, is gone,” Yellowstone National Park Deputy Superintendent Pat Kenney said in a statement.

It was a staffer at another fire lookout on Mount Washburn who spotted the structure burning on Mount Holmes late on the afternoon of July 16.  The Mount Washburn Fire Lookout is staffed seven days a week, mid-June through mid-September. Three other lookouts in the park can be staffed if they’re needed, the Park Service said.

On Wednesday — a day after the Mount Holmes Fire Lookout burned down — Yellowstone’s first wildfire of 2019 was reported east of Canyon Village. With the small 7 Mile Hole Fire smoldering on a steep rocky slope above the Yellowstone River, firefighters plan to monitor the situation from the rim of the canyon.

It, too, was started by lightning, park officials said.