By and far, Alcatraz Island looks A LOT smaller than it really is from a distance. Expect to spend 2-4 hours walking the highlights of the 22-acre island, wear comfortable shoes, and depending on the time of year, layers of clothing. We were very lucky during our stay in that the fog cleared up perfectly by late morning, making for a gorgeous day.
The perspective vistas of the island were amazing! We definitely got our exercise that day going up-and-down all the hills, stairs, and paths inside and out the prison. I didn't know that in the 1970's, Alcatraz was occupied by Native American Indians as an act of reclamation activism. They lived on the island for 19 months!