Grubb built two forges on Hammer Creek, called the Upper and Lower Hopewell Forges, to complement his Cornwall Iron Furnace that began operation in 1742. His mansion still stands nearby.
Hopewell became an integral part of the Grubb family's ironworks. Founded by Peter Grubb, it was owned and operated after 1765 by his sons, Curtis and Peter. Peter Jr. lived in the mansion and ran the Hopewell Forges while Curtis lived at Cornwall and operated the Cornwall Iron Furnace.
Robert Coleman acquired most of the Grubb properties beginning in 1783, including the Hopewell Forges in 1802. While it is unclear when Hopewell ceased operations, historians have documented that it produced 250 tons in 1833. It is likely that it was closed before 1854 when Coleman's Speedwell Forge near Hammer Creek was shut down.
There is little left of the forges today except a few remnants of the dams at the creek. But Peter Grubb's "Hopewell Forge Mansion & Historic Marker". can still be seen on present-day Route 322.