Occupation of Alcatraz manhood." Some 50 of the Alcatraz occupiers traveled to the East Bay and began an occupation of an abandoned and dilapidated Nike Missile installation located in the hills behind the community of Kensington in June 1971. This occupation was ended after three days by a combined force of Richmond Police and regular US Army troops from the Presidio of San Francisco. Moreover, the Alcatraz Occupation greatly influenced the American government's decision to end its Indian termination policy and to pass the Indian Self-Determination and Education Assistance Act of 1975. The Alcatraz Occupation led to an annual celebration of the rights
Alcatraz Island self-determination, in part as a result of the publicity and awareness created by the occupation. The occupation ended on June 11, 1971. The entire Alcatraz Island was listed on the National Register of Historic Places in 1976, and was further declared a National Historic Landmark in 1986. In 1993, the National Park Service published a plan entitled "Alcatraz Development Concept and Environmental Assessment." This plan, approved in 1980, doubled the amount of Alcatraz accessible to the public to enable visitors to enjoy its scenery and bird, marine, and animal life. Today, American Indigenous groups, such as the International Indian Treaty