It's probably the most famous prison on Earth.
Alcatraz is widely regarded as having been inescapable during its years of operation between 1934 and 1963.
Well, according to the FBI anyway. Evidence recently emerged of 'missing, presumed drowned' inmate, John Anglin, living freely since his escape in 1962.
But for two young daughters of one of the prison's former guards, what was it like to grow up on The Rock?
Mary and Jean Comerford spent 13 years living on the island with their mother, father and elder sister, Carol, after their father moved them from the Bronx in New York to become one of Alcatraz's correctional officers.
"My parents sold everything they had and drove across the country. I was three weeks old," Mary told Soroptomist International.
"This was before the interstate highway system and also before disposable diapers and formula. They were real pioneers."
Her sister, Jean, said they had far better homes on Alcatraz than the kids whose dads worked at the prison but who lived in San Francisco on the mainland just two kilometres away.
"We had a beautiful building that we lived in - three bedrooms, hardwood floors and beautiful views," she said.
"I loved the island. Our views were so great. I thought one side of the world was San Francisco and the other side was the East Bay and we lived in the centre of the Earth. It was just grand."
She said they often even interacted with the prisoners - some of the most dangerous on Earth, sent to Alcatraz specifically so they could never get out.
View from the mess hall to the kitchen at infamous Alcatraz prison. Credit: PA
"I actually remember a couple by name: Pat and Flat Top," Jean said.
"They would do various jobs around the island, repairing this and that. Prisoners would even come into our house to collect our garbage without a guard.
"My cousin, Jim, spent two summers with us. He said to my mother one day, 'Oh, there's someone in the kitchen', and she said, 'Yeah, that's just one of the prisoners'."
As kids, they spent many hours playing on the huge, flat, concrete 'Parade Ground' - an area of flattened land that was part of plans that were later abandoned to turn the whole island into shell-proof underground magazines in the 1800s.
When the Comerfords were on the island, it was home to see-saws and swing sets.
But their time on Alcatraz wasn't all fun and games.
Just 11 days before Mary's fifth birthday, the best laid escape plans of inmate Bernard Coy were put into action. This set off the three-day 'Battle of Alcatraz'.
Bernard Coy. Credit: Police Shot
"I was playing on the Parade Ground and all the kids were out there playing when we heard a whistle go off," she said.
A midday whistle was sounded every day at 12. But this one blared out after 2pm.
"We were little kids, we didn't really pay any attention," Mary said. "But one of the mothers knew that there was trouble in the prison and grabbed us all."
Coy and his accomplices had overpowered guards to gain access to the weapons room before trying to find keys to the outer yard door through which they could escape. However, they became trapped and, in desperation, decided to battle it out.
The Comerfords' father, a tower dock guard at the time, was shot and injured and had to play dead overnight before he could escape.
"One of the mothers had the brilliant idea of contacting the red cross to help us," Mary said.
"But because it was such a huge event there were reporters everywhere. One of them refused to get off the pay phone to his paper.
"They had to get one of the army officers to ask him to move, and when he refused again he dragged him out by the collar and said to us, 'The phone is free now'."
Despite the drama of 1946, they said they were heartbroken to leave the tight-knit community of families living at Alcatraz.
Gangsters, killers and thieves around every corner. They said they couldn't have wished for a nicer home.
Words: Nathan Standley