1975 : President Ford signs Grand Canyon National Park Enlargement Act, Grand Canyon and Marble Canyon National Monuments are absorbed into the park
1976 : Annual visitation exceeds 3,000,000
1986 : Mid-air collision between sightseeing helicopter and small plane killing all passengers
1989 : Operators of Glen Canyon Dam are instructed to assess dam operations and ways to minimize impacts to the Grand Canyon
1991 : National Park Service begins drafting a new general management plan to guide future administration of the park
1991 : President George Bush visits Grand Canyon to witness the signing of a landmark agreement to minimize air pollution coming from Navajo Generating Station
1992 : Annual visitation exceeds 4,000,000
1993 : Annual visitation misses 5 million by only 70,000
1994 : Grand Canyon National Park pages go up on World Wide Web :-)