When people think of earthquakes in the United States, their minds often go to California or Alaska — not the heartland of Ohio. Yet, on March 9, 1937, Ohio experienced its most powerful and destructive earthquake in recorded history. Centered near the small town of Anna in Shelby County, this seismic event shook the state to its core and left an indelible mark on its residents and infrastructure.
The Earthquake Strikes: March 9, 1937
At precisely 9:45 p.m., a 5.4 magnitude earthquake struck western Ohio. While that number may seem moderate compared to the earthquakes that hit the West Coast, it was extremely strong for the Midwest — a region not typically associated with seismic activity. The quake was felt across multiple states including Indiana, Kentucky, Illinois, and even parts of Michigan.
What made this earthquake so destructive wasn’t just the magnitude, but also the shallow depth at which it occurred. Shallow quakes tend to be more damaging because their energy is closer to the surface and buildings are more susceptible to shaking.
The Village of Anna: Epicenter and Ground Zero
The small village of Anna, with a population of only a few hundred at the time, was at the center of the chaos. Local schools, churches, and homes suffered significant structural damage. Walls cracked, chimneys collapsed, and frightened residents ran out into the streets as the earth beneath them trembled violently. In the days following the earthquake, Anna earned a grim nickname among geologists: “The Earthquake Capital of Ohio.”
Anna’s schoolhouse, in particular, became a focal point of the event. The building sustained such severe damage that it had to be rebuilt — not once, but twice, due to repeated seismic activity in the years leading up to and following the 1937 quake. Ultimately, engineers rebuilt the school with advanced earthquake-resistant designs, making it one of the first such buildings in the region to incorporate those features.
Damage Beyond the Epicenter
Although Anna took the brunt of the impact, the quake’s effects were widespread. In nearby Sidney and Wapakoneta, buildings suffered cracked walls and shattered windows. In cities like Columbus, Dayton, and even as far as Cincinnati, residents reported swaying furniture, swinging light fixtures, and general panic.
Fortunately, despite the considerable structural damage, there were no fatalities. However, the quake did leave several people injured and caused hundreds of thousands of dollars in property damage — a considerable sum during the Great Depression era.
The Science Behind the Shock
Ohio lies near the ancient Grenville Fault Zone and the New Madrid Seismic Zone — both of which can contribute to intraplate earthquakes. These are earthquakes that happen away from the edges of tectonic plates and tend to be less frequent but widely felt when they do occur.
The 1937 earthquake helped scientists better understand seismic risks in the Midwest. Prior to that, many experts believed the region to be geologically quiet. This event, along with a series of smaller tremors that followed in subsequent years, changed that perception. It also triggered new studies into the fault lines crisscrossing beneath Ohio’s surface.
The Lasting Impact on Ohio’s Preparedness
The earthquake spurred a wave of changes in Ohio’s approach to earthquake preparedness. Building codes in the region were gradually updated to consider the risk of seismic activity, especially in areas like Anna and Shelby County. Schools and public buildings began incorporating earthquake-resistant features, such as reinforced foundations and flexible support systems.
Additionally, local governments invested in better monitoring systems. The Ohio Seismic Network (OhioSeis), formed much later in 1999, now tracks earthquake activity across the state using a series of seismic monitoring stations.
Earthquakes in Ohio Today
Although large earthquakes are rare in Ohio, the state still experiences minor tremors every year. According to the Ohio Department of Natural Resources (ODNR), more than 200 earthquakes have been documented in the state since 1776. Most of these are too small to be felt, but a handful have exceeded 4.0 in magnitude — enough to cause concern and sometimes minor damage.
In recent years, some earthquakes in eastern Ohio have been linked to fracking and injection wells, raising both environmental and safety concerns. These developments have renewed interest in earthquake preparedness across the region.
Conclusion
The 1937 earthquake that struck Anna, Ohio, stands as a stark reminder that no region is entirely safe from the forces of nature. It was a moment that changed not only the landscape of a quiet Midwestern town but also the way Ohioans thought about seismic risk.
Today, the earthquake is commemorated in Anna through local history displays and is studied by geologists and emergency planners alike. While Ohio may not see frequent earthquakes, the legacy of that powerful event continues to influence building practices, preparedness efforts, and our understanding of the state’s hidden seismic vulnerabilities.
It may have happened nearly a century ago, but for those who lived through it — and for the generations that followed — the memory of Ohio’s biggest and most damaging earthquake remains deeply etched in the state’s history.