In an old mule stable in the Presidio, history will leap to life this weekend in the shape of rusty old spoons, World War I gas masks and original tickets to the 1915 Panama-Pacific International Exposition. And more.

The national park’s museum is trotting out its treasures for the public on Sunday and Monday in a free show that happens only once a year. If history geekhood is your wish, this is your answer.

On one table, a perfectly preserved Spanish-American War hat will take you back to 1898 with its jaunty gold acorn rim band and button reading, “Certo Ictu Dirigo.” (Latin for, “I aim with a sure blow.”) On another, the six tiny sharpened spoons that three prisoners used to dig their way out of Alcatraz prison in 1962 will demonstrate, as only in-your-face reality can, why it took six months for those crafty cons to get the job done.

A sparkling green crystal from the 435-foot-tall “Tower of Jewels” hints at just how magnificent the centerpiece of the 1915 Panama-Pacific extravaganza was. There were 102,000 of them, lit up at night by 50 searchlights like something out of Oz.

Echo of Cold War

A century-old green swimsuit from the fabled Sutro Baths recalls the modesty of yesteryear, Ohlone Indian arrowheads evoke the difficulty of bagging dinner centuries ago, and Nike missile parts from the 1950s echo the Cold War in chunky, steely menace.

Presidio museum artifacts When: July 17 and 18, 10 a.m. to 4 p.m. Where: Archives office in the Presidio, Building 667 at the corner of McDowell Avenue and Cowles Street. Admission: Free

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There are also pictures galore showing the cells from which the Alcatraz inmates escaped, the 1913 “Gravity Car” that took tourists on rails 8 miles down Mount Tamalpais to Muir Woods, and, of course, many slices of military life, including soldiers shooting skyward on Space Age jet packs in the 1960s.

The artifacts are among 6.5 million maintained by what is officially known as the Golden Gate National Recreation Area Museum Program. It’s one of the biggest national park collections in the country, and most of it resides in a two-story brick building at the Presidio that housed up to 102 mules when the park was an Army base.

The collection encompasses everything that has to do with archaeology, natural history, culture and the military heritage of lands touched by the park, which is why Alcatraz and such far-flung locales as Bolinas and Woodside are fair game. The building even has a hefty selection of butterflies mounted on pins, including the delicate and endangered Mission Blue.

There’s also a batch of more sensitive materials at a separate location — including the delicate, deteriorating dummy heads the Alcatraz escapees used to fool guards into thinking they were in their cell beds. But curator Amanda Williford keeps that place close to her vest.

“It’s a secret and, no, there are no aliens there,” she said. Some of its bounty will be trucked over for the two-day show.

As with most things to do with national parks, there’s an educational purpose to this event, and Williford is more than a little stoked at the idea of visitors streaming in to her building near the bay-side edge of the park. It’s usually so quiet that bird chirps stand out, and her staff of four is too small to be able to show everything off more than once a year.

‘It’s just cool’

“We are preserving people’s history here, making sure their stories don’t get untold through the years,” she said. “Yes, we have a lot of stuff, a lot of objects and archives on everything from architecture to the military, but it’s really, in the end, about the men and women who make things run. It’s just cool.”

Williford also likes to remind people that this history thing can get personal, too.

“I’m a huge enabler of anyone who wants to learn about history or do research,” she said. “And if you come in for the exhibit, we can have all kinds of conversations about saving your own stuff, too. We can talk about acid-free folders, properly sleeving your photographs, making sure you have the right documentation.

“History is for everyone. It’ll be fun!”

Kevin Fagan is a San Francisco Chronicle staff writer. Email: kfagan@sfchronicle.com