Siegenthaler-Kaestner Esker State Nature Preserve is a 37-acre protected site in Champaign County, Ohio, valued for an unusual concentration of glacial landforms. Within this compact landscape are an esker, a kame, and a kettle, three classic features formed during the last Ice Age. Its most prominent feature, the winding esker, was created by sediments left in an ancient stream channel that flowed within or beneath a Wisconsinan glacier roughly 11,000 to 25,000 years ago. When the glacier vanished, the ridge remained. The preserve is significant as a clear small-scale example of how ice and meltwater shaped Ohio’s terrain.