Gregg Township municipal offices are located at 3586 Penns Valley Road, Spring Mills PA 16875.
Gregg township was erected in November, 1826, out of portions of Potter, Miles and Haines townships and named in honor of Hon. Andrew Gregg, a resident of the township who had been a member of Congress from 1791 for sixteen years and United States Senator from 1807 to 1813. Its earliest settlers were George Woods in 1774, and George McCormick who settled at Spring Mills in 1773 and built the first mill there. It is a rich agricultural township. Penn's creek rises in the northern portion, its source a miniature lake in a cave. Penn Cave is now a noted place of resort. Township post-offices are Spring Mills, Farmers Mills, and Penn Hall. Population in 1850, 1473; in 1860, 1556; in 1870, 1636; in 1880, 1795; in 1890, 1688.