Construction underway on the main building of St. Charles Seminary in Mercer County, originally opened in 1922. Rooted in the county’s history since 1861, the seminary remains a cherished landmark for faith and community.

Discover the Rich Heritage of Celina and Mercer County

Welcome to the Celina-Mercer County Historical Archive, your gateway to the rich history of Celina and Mercer County, Ohio. Discover the stories that define our communities, from Celina’s founding on the shores of Grand Lake in 1834 to its growth as a hub of commerce and culture.

Explore the unique heritage of our towns and villages: experience Maria Stein’s deep German Catholic traditions, reflected in the iconic Shrine of the Holy Relics. Uncover Fort Recovery’s origins on the site of a pivotal battle of the Northwest Indian War, and learn about Coldwater’s transformation from a crucial railroad hub to a vibrant center of local business.

Delve into St. Henry’s agricultural roots and community spirit, follow the pioneer path of Rockford—originally known as Shane’s Crossing along the St. Marys River—and discover Mendon’s origins as the village of Guilford. Explore Montezuma’s close connection to Grand Lake, which supported the Miami and Erie Canal and spurred local growth.

From early settlements and frontier resilience to modern-day achievements, the Celina-Mercer County Historical Archive captures the stories that connect us all and celebrate our shared heritage.

THIS MONTH’S FEATURED DIGITAL EXHIBIT

Breakwaters and Big Ideas: Leo Dwyer’s Grand Plan for Grand Lake

A bold plan once promised to transform Grand Lake into a premier destination—complete with breakwaters, roadways, and artificial islands. Backed by civic leader Leo E. Dwyer and a coalition of local and state advocates, the 1934 Grand Lake improvement proposal aimed to lift western Ohio’s economy in the depths of the Great Depression. Though never fully realized, the vision offers a striking glimpse into the ambitions, politics, and people that shaped the lake’s past—and echoes a legacy still visible today.

Explore the Digital historical Collections

Discover the Celina-Mercer County Historical Archive and explore curated collections of books, photographs, maps, and documents that reflect the history of Mercer County. Whether you’re looking to uncover local stories or simply curious about the past, our digital historical collection offers a window into the rich heritage of our community.

Select a collection below to begin exploring today.

Historic Marion Township map