In the years leading up to the Civil War, several homes and farms in Illinois functioned as stopovers on the Underground Railroad, the network of hiding places for runaway slaves on their way to freedom in the north. One of these was the Graue Mill on Salt Creek in what is now Oak Brook. The mill, which was often very busy, was next to a stagecoach shop. Customers would park their horses and visit while the escaped slaves hidden in the mill’s basement tried to remain quiet. Now known as the Old Graue Mill and Museum, it’s one of the area’s most well-known former Railroad sites and features an exhibit on the mill’s history in the basement. Other “stations” were more elaborate, such as a house in Glen Ellyn on the Du Page River described in history books as being constructed out of concrete and soundproofed by sawdust and grass, with an escape tunnel running from the house to a barn. But the house, like other former stations in McHenry County and Chicago, is long gone.

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Turner says it’s impossible to determine how many people passed through Illinois’ Underground Railroad system or how long they stayed in each place. “I see it like jazz, in that every situation was different and people were resourceful and met whatever the need was,” she says. Some spent the winter in the area before continuing to Detroit in warmer weather. Others stayed less than a day to avoid capture.