Weathering the State Penitentiary: Examining the conditions inside the walls

The entrance of the penitentiary is also made of same limestone as many of the housing units.

Claimed to be the bloodiest 47 acres in America and once home to 4,900 inmates at its peak, the Missouri State Penitentiary has weathered extremely hot summer, bitterly cold winters, and severe storms for 182 years.

With such a historic past, the questions stands as to how mid-Missouri's diverse weather impacted the operation of the Missouri State Penitentiary.

<="" sd-embed="" contenteditable="false">

Michael Groose served as the final warden for the Missouri state Penitentiary until 2004. Fourteen years later, Groose is a tour guide, walking the same cell blocks he did for 32 years.

Built in the 1800s, one of the oldest buildings at the prison is housing unit 4, also know as 'A-Hall.' The building has a white exterior and has a thick walls made of limestone, like much of the older buildings. The white exterior does help to reflect the sun's rays, but as Groose explained, the rock this structure was able to take in the sun's heat just as well.

<="" sd-embed="" contenteditable="false">

"In the early days, there were simply no utilities," Groose said. "There was no air conditioning, there was no electricity. And there was no plumbing, there was no heat systems and so they were really subject to the conditions of living almost outdoors."

<="" sd-embed="" contenteditable="false">

And with little to no circulation or utilities in the early years of the prison's operation, summers were unbearably hot both outside and inside. In an old building like A-Hall, sunlight would be the main factor in how the temperature fluctuated inside the building. It was also the key factor in the common "warm air rises, cold air sinks" principle understood today. Sunlight would unevenly heat up the air inside the building, allowing warm air to rise, and cooler air to fall.

But, there was a way for inmates to help control the temperature of their cells, by using paint to make temporary heat curtains. Inmates were given different colors of paint for decorative purposes, but this paint was more so used to cover windows, and not walls.

Groose explained how in the spring, inmates would paint the windows of their cells to block the summertime sunlight. Then, in the winter, they would peel back the paint to allow as much sunlight to shine in. While this provided a little bit of relief, it was uniformly done throughout the prison.

<="" sd-embed="" contenteditable="false">

Though the summer heat was unbearable at times, it was not as potentially deadly like the cold in winter months. Early in the prison's operation, inmates worked in the local rock quarry to excavate limestone for the prison. Then, inmates would use the rock and build the prison year round with little protection from the elements.

When asked, Groose said there had to have been weather-related deaths at the prison and mostly in winter.

"These people worked in the rock quarry, building this penitentiary. In January, when it is 15 degrees outside and one is working several hours in the cold, if that were you coming home, you'd go into the nearest heat register or heat source they had none here," he said.

Furthermore, inmates owned very little, so the best they could do to warm back up is cover up with everything they owned.

Later in the prison's operation, more modern accommodations were introduced to help those living inside. An ice plant was built in the mid-1900s.

"We let them have an almost unlimited supply of ice," Groose said. He explained how workers routinely made routes throughout each cell block to make sure the ice bins were kept full of ice.

<="" sd-embed="" contenteditable="false">

While learning about how the heat and cold impacted daily life, only the question of severe weather plans was left.

Groose explained that there were many configurations in place for different weather events and situations. But in terms of this prison, he said this: "It'd take a tank knock them down. They realize, too, when you walk up to a housing unit and see that the sill is 14 inches thick, they realize that this building is not going anywhere." So, their weather plan was to stay put and shelter in place in the event of a severe storm.

And with that, the Missouri State Penitentiary will weather the storm for years to come.

If you have an idea for a with history segment, share it with us on our Facebook page here or send us an email to

For more information on tours at the Missouri State Penitentiary, visit the website here.

close video ad
Unmutetoggle ad audio on off