The Houdaille Quarry is a 120-acre (49 ha) former rock quarry located in Springfield Township, Union County, New Jersey bordering the northern edge of the Baltusrol Golf Club.[1][2]
Bisected by Interstate 78, it is directly east of the Watchung Reservation and touches the Summit border as well as Hidden Valley Park.
Owned by Union County, New Jersey[1] and typically closed to the public aside from occasional ecological tours, it is called the “Grand Canyon of Union County."[3]