A Day at the Old Idaho Penitentiary: Exploring Idaho’s Untold History

For most people, Idaho is known as the Gem State and for its famous potatoes, but in Boise there are a few other gems worth digging up. During a recent trip through the area, we stumbled upon the Old Idaho State Penitentiary Museum and the two museums that share the property: the Idaho Museum of Mining & Geology and the J. Curtis Earl Weapons Museum. It’s an unexpected mix, but together they offer a surprisingly engaging look at Idaho’s lesser-known history. With that in mind, we headed in to see what the place was all about.

The Idaho Museum of Mining & Geology

A Tiny Museum With Plenty to See

Our tour began with the Idaho Museum of Mining and Geology just outside the prison’s main entrance. It’s the smallest of the three museums, but there’s more to see than you’d expect. Cases of crystals, gemstones, and mineral specimens line the main room, each one showing off a different shade of Idaho’s geological personality. There are even a few interactive displays, which is always fun for those of us with curious fingers. And even if you’re not a rock collector, it’s easy to appreciate the variety of specimens in the exhibits.

Idaho’s Underground Story

The museum guides you through the state’s mining history, from gold rushes and volcanic activity to fault lines and the geological quirks that earned Idaho its “Gem State” nickname. It’s a lot to take in, but it gives you a sense of how much of the area’s identity was shaped long before it became the Idaho we know now.

A Glimpse Beyond Earth

Alongside the minerals and mining exhibits, the museum also features a small collection of meteorites – a reminder that not all of Idaho’s rocks originated in Idaho.

It’s a fascinating addition that offers an intriguing look at the forces that shaped the region, both below and above the surface.

The Old Idaho State Penitentiary

After wrapping up the mineral museum, we made our way toward the main attraction, the prison itself. Walking through the gates of the Old Idaho Penitentiary feels like crossing into a distant, forgotten time. The rusted iron bars and sandstone walls, shaped by the inmates themselves, rise around you with a kind of silent, unpolished authority. As you move farther into the main area, there’s a calmness to it, but the place doesn’t let you forget its past – you can feel it in the air.

The Yard

The main yard is open and exposed, with the buildings forming a rough perimeter around the space. Interpretive signs throughout the grounds remind you that this quiet area once saw riots, attempted escapes, strict enforcement, and more than a few tense moments. The contrast between the present peace and the past chaos is part of what makes the site so interesting.

A Century of Stories

What began as a single-building jail eventually grew into an entire prison complex. More than 10,000 criminals passed through the Old Idaho Penitentiary during its 101 years of operation (1872–1973), bringing with them the stories, conflicts, and complications that helped shape its history.

The prison saw everything from overcrowding to rising tensions, including the full-blown riots in the early 1970s that ultimately pushed the facility to close its doors for good.

Where the Walls Close In

Many of the structures here were designed to hold the prison’s most high-security inmates, and even from the walkways and viewing areas, the atmosphere is unmistakable.

Narrow tiers, steel doors, and tightly packed cells make it clear how harsh conditions were for the inmates housed here. And if you stepped out of line, you could find yourself in an even smaller cell as punishment.

The Inmates

As with other long-running penitentiaries, several high-profile offenders lived and died here. Raymond Snowden, Idaho’s own “Jack the Ripper,” was executed here in 1957 after being convicted of murder, though he was suspected in several others. Lyda Southard, one of America’s earliest known female serial killers, served about ten years for poisoning multiple husbands and relatives before being paroled in 1941. The list goes on, and each one adds another layer to this unique little Big House.

The Women’s Ward

Tucked into its own section of the property, the women’s ward is surprisingly small – just a handful of cells, its own kitchen, and a shared common room. Women were housed here until 1968, and the exhibits highlight the challenges they faced, from limited resources to the occasional escape attempt. It’s a tight space but gives you a clear sense of what life looked like for the women held here. The prison eventually stopped housing women due to health and safety concerns and growing unrest among the other inmates.

Work, Routine, and Survival

Daily life here pretty much revolved around work and keeping yourself occupied. Baking, sewing, stamping license plates (yes, they really did that), and even building the very walls that confined them were all ways to stay busy and out of trouble. Some inmates even ran small shops out of their cells, including the one that served as the prison barbershop.

Riots and Rebellions

The prison endured several major riots, including the 1973 uprising that led to its closure. Accounts from the time describe a system stressed by overcrowding and worsening conditions. Even the contraband on display, from shanks to improvised tools,  shows just how volatile daily life could be.

Overall, our time at the Old Idaho Penitentiary was both sobering and strangely captivating. Unfortunately, we missed the last guided tour of the day, so access was limited. But even just walking the grounds was enough to feel the weight of this place – its stories, its scars, and everything that happened here.

The J. Curtis Earl Weapons Museum

Guns a’ Blazin’!

After the intensity of the prison excursion, the weapons museum wastes no time shifting the mood. Tucked into a back corner of the prison grounds, the J. Curtis Earl Weapons Museum hits you the moment you step inside, with rows of antique firearms, military munitions, and experimental weapons packed into every case and lining every wall.

Once you get past that first wall of rifles, things escalate fast. Suddenly you’re staring down the barrels of mounted machine guns and detailed displays of early firepower.

The museum even had a pair of well preserved blunderbuss guns – a type of early shotgun that could fire just about anything you could cram down the barrel, like rocks, nails, or even silverware. Brutal, but very effective. It’s the kind of display that makes you slow down, lean in, and realize just how quickly weaponry evolved over the centuries.

Women in Military History

This part of the museum shifts the focus from firepower to woman power, shining light on the women who served, from early trailblazers of the Wild West to the recruits who filled essential roles during wartime. The uniforms, posters, and personal accounts give this section genuine depth, showing how women’s contributions grew from support roles to the wide range of positions they hold today.

If you enjoy wartime memorabilia or simply appreciate the history behind military weapons, this is a museum you’ll definitely want to explore. Even for the non‑gun crowd, the stories behind their inventions are surprisingly engaging. And since it’s included with the prison admission, it’s an easy stop that adds a whole new level to the experience.

Final Thoughts

The Old Idaho Penitentiary complex is one of those places where you arrive expecting a simple walk through an old prison, and instead you get a lesson in geology, incarceration, guns, and a richer understanding of Idaho’s lesser-known past, full of stories that linger long after you leave. It’s a stop that stays with you, especially when you think about the people behind those stories, not just the walls that held them.

And while you’re in the area, visit downtown Boise, grab a bite at one of the city’s many fantastic restaurants, or enjoy some outdoor activities along the Boise River Greenbelt.

And for more museum adventures, check a few of our favorites, like Rosicrucian Egyptian Museum in San Jose, CA, Asian Art Museum in San Francisco, CA, or USS Hornet Museum in Alameda, CA to start with. What are some of your favorite museums? Comment below & subscribe to our blog for more!