 In 1961, the Pennsylvania Department of Highways approved moving the northern terminus of PA 68 to US 6 in Kane, with PA 321 replacing much of the route north of Kane.The former northern terminus at PA 59 in Kinzua was inundated with the creation of the Allegheny Reservoir.In 1970, the north end of PA 68 was cut back to its current location at US 322 in Clarion, with the route between US 322 northwest of Clarion and US 6 in Kane replaced by a rerouted PA 66.