The Pahaquarry Copper Mine is an abandoned copper mine located on the west side of Kittatinny Mountain presently in Hardwick Township in Warren County, New Jersey in the United States. Active mining was attempted for brief periods during the mid-eighteenth, mid-nineteenth, and early twentieth centuries but was never successful despite developments in mining technology and improving mineral extraction methods. Such ventures were not profitable as the ore extracted proved to be of too low a concentration of copper. This site incorporates the mining ruins, hiking trails, and nearby waterfalls, and is located within the Delaware Water Gap National Recreation Area and administered by the National Park Service.