They called it "The Rock"-a brooding, fortress-like prison on a rocky little island in San Francisco Bay.
Until it closed in 1963 and became part of the Golden Gate National Recreation Area, Alcatraz was home to some of the nation's most notorious criminals, including mob boss Al Capone, Birdman Robert Strouss and George "Machine Gun" Kelly.
The facility was escape-proof, or so claimed guards who patrolled the walled fortress with machine guns, bazookas and attack dogs.
Some people think they were mistaken.
Three prisoners who might have beaten The Rock were John William Anglin and his brother, Clarence, apair of holdup men from Florida, and a convict pal, Frank Lee Morris -- a bank robber with a genius IQ. The trio is said to have engineered their breakout without any of the violence of a more dramatic and bloody convict uprising early in 1946 that was put down by guards, police, Marines and shell-fire from two Navy destroyers.
According to some accounts, the Anglin brothers and Mr. Morris dug out of the prison with tablespoons.
After months of gathering gear and planning, the convicts supposedly smuggled spoons to their cells. They spent weeks chipping away at mortar and stone until they opened holes at the back of their cells large enough to squeeze through.
Once they had access through the vents into a utility corridor between cellblocks, they began smuggling in supplies. They pilfered enough raincoats to fashion three sets of water-wings and a waterproof raft during months of work. They also hid away at least one flat wooden plank, for an oar.
The conspirators fooled guards by placing on their pillows dummy heads fashioned from soap, concrete, plaster and cardboard, and hair stolen from the prison barber shop. Then they slipped through the vents into the utility corridor. They climbed metal pipes to the prison roof and clambered down to the rocks.
Alcatraz, which is Spanish for "pelican," was named for the big-billed seabirds that flock to the rocky island. It is separated from the San Francisco shoreline by two miles of dangerous water, roiled to a white froth by winds and deadly riptides. Hammerheads and occasional great whites sharks silently cruise beneath the waves.
It is regarded as one of the most dangerous water crossings on the Pacific coast.
Yet based on evidence found on the beach, the convicts apparently set out on a June night in 1962 in one, possibly two, flimsy liferafts put together from stolen prison raincoats. Shortly after the men were discovered missing, two makeshift life vests, a wooden paddle and a pack of photos were found floating in San Francisco Bay.
Embarrassed prison authorities said the men had either drowned or were eaten by sharks. Nevertheless, Wanted posters were distributed by the FBI.
Alcatraz closed about a year after the daring caper, and most of the prisoners were transferred to a new maximum security institution at Marion, Ill.
In the meantime, there were rumors that one or more of the trio may have survived. In 1986, news stories reported that Clarence Anglin had died in Iowa in the 1970s, according to his grandson. His brother John and Mr. Morris were reportedly eaten by sharks.
The escape attempt was later recounted in a segment of the NBC televison series, Unsolved Mysteries, leading to more reports that one or more of the men may have survived.
In 1990, a San Francisco newspaper quoted a U.S. marshal in Tallahassee, Fla., who confirmed that law enforcement authorities had been looking for the Anglin brothers in northwest Florida for about two years. They're still looking.