Island
This refers to a 19-month-long occupation by members of several Native American tribes in an effort to reclaim Alcatraz Island. Although the occupation was put to an end by federal marshals in 1971, graffiti from the occupation can still be seen on the island's water tower. https://www.nytimes.com/2012/12/25/us/alcatraz-american-indian-occupation-graffiti-preserved.html