This old service station is located on Indiana Highway 38 east of Hagerstown in Wayne County, Indiana. It was built from a diverse array of boulders - it includes chunks of fossiliferous limestone (the long white piece at lower right below), gneiss (the red-and-black banded piece at lower left) and granite (see the many pink-to-red clasts). This diverse set of rocks arrived here thanks to the flow of continental glaciers from the north in the Pleistocene. The granite and gneiss chunks probably came from the Canadian Shield and were carried south in flowing ice during the last two million years. The limestone clasts were probably transported by glaciers too, but they are of a more local origin, because Indiana's bedrock includes much Ordovician and Silurian limestone. Retreat of the glaciers left behind till covering much of the Hoosier landscape, and the till includes boulders like these. Such boulders are commonly carried by farmers to the edges of their fields and left there, but these boulders were put to work in the building trade.

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