This grist mill was built in 1809 for John Knabb and was acquired around 1875 by John Bieber by his marriage to Maggie Knabb. Their fourth son, Effinger Bieber, inherited the property. He married Mary Moyer. They ran the mill until his death in 1996. Mary continued to run the mill until her death in early 1998. Like Effinger, she was in her 90s when she died. Up until the time of her death the mill was producing commercially and continuously since its construction, for nearly 190 years.
The mill equipment is powered by water from the Monocacy Creek. The mill sits on a property of approximately 25 acres on Bieber Mill Road in the Oley Valley of Pennsylvania.