A Santa Ana-wind-fueled fire that started at dawn Wednesday in California’s Simi Valley narrowly missed the Ronald Reagan Presidential Library and Museum, which is filled with irreplaceable historical artifacts.

Melissa Giller, a spokeswoman for the library, told the Associated Press that aerial water drops and a firebreak protected the complex from damage from the Easy Fire. By the afternoon, aerial footage showed a blackened and burned area completely surrounding the unscathed library.

A herd of goats is brought in every year to eat the brush to create the firebreak, she said.

Earlier in the day, executive director John Heubusch told the CBS Los Angeles affiliate the fire was “encircling” the Air Force One Pavilion in the library complex, which holds a Boeing 707 aircraft used for decades as the presidential plane.

“It’s a national treasure, so hopefully the heroes out here — and the helicopters and trucks that have surrounded the library are — they’re doing a magnificent job,” Heubusch said.

The library and museum complex is filled with national treasures. Here are some of the things firefighters are worked to save:

— The aircraft used as Air Force One for presidents Richard Nixon, Gerald Ford, Jimmy Carter, Ronald Reagan, George H.W. Bush, Bill Clinton and George W. Bush.

— A steel beam recovered from Ground Zero after the 9/11 terrorist attacks.

— A helicopter once used as Marine One. This particular helicopter carried President Lyndon B. Johnson and President John F. Kennedy’s casket after his assassination in 1963.

— A large section of the Berlin Wall.

— The gravesite of Reagan and former first lady Nancy Reagan.

Perhaps most concerning to history lovers was the threat posed to the Reagan Archives. Administered by the National Archives, the repository holds a stunning amount of material from Reagan’s two terms as commander in chief, including:

— 60 million pages of documents.

— 1.6 million photographs.

— Half a million feet of film.

— Tens of thousand of audio and video tapes.

— More than 40,000 additional artifacts, including campaign bumper stickers and a lacquered samovar from Soviet president Mikhail Gorbachev.

Presidential archives are invaluable resources to historians, journalists and other researchers seeking to understand American history. Much of the Reagan collection has yet to be explored. Historians on Twitter expressed alarm at the thought that some of it could be lost forever.

Yale historian Glenda Gilmore compared that prospect to the loss of the 1890 census records, which were destroyed by fires in 1896 and 1921. According to the National Archives, that particular census was likely the most important for historians to understand immigration, industrialization and westward migration in the United States.

The Reagan Library, which is the largest of all the presidential libraries, may have already lost tens of thousands of artifacts. In 2009, a National Archives inspector general concluded a “near-universal” security breakdown meant library officials could not find or account for tens of thousands of items, the Los Angeles Times reported.

As news of the fire spread, so did well wishes for the first responders battling the blaze.

Fox News anchor Bret Baier held a lecture and book signing there Tuesday night, only hours before the fire broke out. He tweeted well wishes to the first responders Wednesday.

In 1993, the Reagan family held a celebration at the library to honor firefighters who had battled similar blazes that year, according to the Los Angeles Times. The president’s daughter Maureen Reagan, had this to say at the time: “We live in a place with unique terrain that’s continually touched by fire, and thank God we have unique and special men and women that are trained to stop those fires when they threaten people.”

By 11 a.m. Wednesday, more than 800 firefighters were battling the blaze.

This article has been updated.

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