when did alcatraz close

Alcatraz Federal Penitentiary closed on March 21, 1963. The closure was due to the prison being too expensive to operate, structural deterioration from saltwater exposure, and concerns about escape attempts, especially after a famous escape in June 1962 when three inmates fled and were never found. The high cost of transporting staff, food, and supplies to the island also contributed to the decision to shut it down. After closure, the remaining inmates were transferred to other prisons, and Alcatraz later became a public museum and tourist attraction.