Alcatraz audio guide,
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Look north across the water, past the ends of the piers, and find the low rock with a long pale building along its top. That is the whole of it. Twenty-two acres, one thousand six hundred and seventy-five feet from end to end, about a mile and a quarter offshore.

The long block on the crest is the cellhouse. The white tower at the southern end, the end nearest the city, is the lighthouse, and the water tower on its steel legs stands over on the island's northwestern side. Behind all of it rises the big hill of Angel Island, where the Army quarried sandstone for the fort.

Because a fort is what this was first. When gold was found in 1848, San Francisco went from three hundred people to thirty thousand in a few years, and the bay became a prize worth defending. Army engineers planned a triangle of forts to guard it. One corner, at Lime Point, was never built, because the government and the landowner could not agree on a price. Alcatraz was finished first, and it became the most powerful defence on the Pacific Coast. An engineers' report of 1852 put the logic plainly: any ship heading for the city had to pass within a mile of this rock. Eleven cannons went up in 1854. By the early 1860s there were a hundred and eleven.

They never fired at an enemy. The nearest they came was in October 1863, when an unidentified warship, her flag hanging limp in the still air, was towed into the bay by men in rowing boats and turned towards Angel Island. The captain on Alcatraz fired a blank, then an empty shell across her bow. She answered with a twenty-one-gun salute. She was the Sutlej, flagship of the British Navy in the Pacific, and Alcatraz saluted back.

The name is older than any of it. In 1775 the Spanish explorer Juan Manuel de Ayala charted the bay and named an island Isla de los Alcatraces, usually translated as the island of the pelicans, though the old word may have meant gannets. Ayala actually gave the name to what is now Yerba Buena Island. An English naval officer, Frederick Beechey, later attached it to this rock, and it stuck.

What turned the fort into a prison is the water between you and it: fifty-three degrees Fahrenheit, and fast. By 1861 the island was the military prison for the whole Department of the Pacific. As the boat comes in, keep your eyes on the big building right on the waterfront. That is where you land.

Stand in the middle of the corridor and look straight down it. Cells on both sides, stacked three tiers high, the upper two behind railings, the roof far above. The men who lived here named this corridor Broadway. The one along A-Block was Michigan Avenue, the one in D-Block was Sunset Strip, and at the far end, where everyone massed under a clock on the way in to meals, was Times Square. Find the clock.

Broadway had the least privacy in the building, because the whole prison walked past it to eat. Most new arrivals started one tier up in B-Block, under three months of quarantine, with no visitors for at least ninety days.

Now look at a single cell front. Five feet across. Inside, nine feet deep and seven high, with a bed, a small desk, a washbasin and a toilet on the back wall. The cells were designed so that none of them touches an outside wall. For almost the whole life of the penitentiary there was no hot water in them; the taps went in during the early 1960s, shortly before it closed.

The building is older than the penitentiary by more than twenty years. The Army began it in 1908 and finished it in 1912, using its own prisoners as the workforce, under a construction engineer, Major Reuben Turner. Six hundred cells, a kitchen, a dining hall and a hospital, all in reinforced concrete, and when it was finished it was the largest reinforced concrete building in the world. It was set on top of the old fort's citadel, whose ground floor, dug into a pit behind a dry moat, became its basement. That is where the legend of the dungeons comes from. Old iron was recycled, too: staircases and a door were kept from the citadel, and old cell bars went into the walls as reinforcement. In 1934 the Bureau of Prisons cut out the Army's cell fronts and put in two hundred and sixty-nine new ones, made from four railway carloads of steel.

It did not hold everyone. In June 1962, Frank Morris and the brothers John and Clarence Anglin hid holes at the backs of their cells behind fake ventilator grilles, climbed into the utility corridor that runs behind the cells, and from there reached the roof. They left papier-mâché heads in their beds, made in their own likeness, and went into the bay on a raft they had built themselves. A fourth man, Allen West, could not get out of his cell in time. The other three were never found, and in 1979 the FBI concluded that they had most likely drowned. Across the prison's twenty-nine years, thirty-six men made fourteen attempts: twenty-three were caught, six were shot dead, two drowned, and five are listed as missing, presumed drowned.

The most violent came sixteen years before Morris. In May 1946 a group of inmates spread the bars of the west gun gallery, took its weapons, and set off three days of fighting known as the Battle of Alcatraz. Two officers, William Miller and Harold Stites, were killed, and three inmates died.

What finally closed the place was money and salt. It cost nearly ten dollars a day to keep a man here, against three at Atlanta. Every drop of fresh water came by boat, and half a century of salt spray was eating into the concrete around you. The penitentiary closed on the twenty-first of March 1963.

Come out of the front of the cellhouse and stop. The concrete tower beside you is the lighthouse, the roofless walls next to it were the warden's home, and straight across the water is San Francisco, a mile and a quarter off. Everything on this island was arranged around that distance.

The light was here before the prison and before the fort's guns. The first Alcatraz lighthouse was a Cape Cod-style keeper's cottage with a small tower on its roof, finished in 1853, and its lens had to sail twelve thousand miles round South America to get here. Michael Cassin lit it on the first of June 1854, and it became the first lighthouse on the Pacific Coast. The earthquake of 1906 damaged it, and the new cellhouse would have blocked it anyway, so in 1909 this octagonal concrete tower went up a little to the south, eighty-four feet tall.

Here is a trick of the ground. From the water the lighthouse looks like the tallest thing on the island, but the water tower is taller; the lighthouse just stands higher. And the keepers had help. Guards up in the watchtowers could see a bank of fog rolling in through the Golden Gate before anyone else, and they would warn the keepers so the foghorns could be started.

The house beside it had fifteen rooms over three floors, tall windows over the bay, a terraced garden and a greenhouse. The park's signpost dates it to 1921; other sources put it later in the decade. All four wardens of the penitentiary lived in it, beginning with James Johnston, a prison administrator who came out of retirement for the job and stayed fourteen years. A trusted inmate did the chores.

It burned on the first of June 1970, during the Occupation by Indians of All Tribes, and so did the lighthouse keepers' quarters and the Officers' Club. How the fires started is still disputed. The occupiers had landed in November 1969 and stayed until June 1971, claiming the island under the Treaty of Fort Laramie of 1868, and while they were here President Nixon ended the federal policy of terminating tribes and turned to self-determination instead, partly because of the attention this island drew. The National Park Service counts those nineteen months as perhaps the most influential period in the island's history.

The lighthouse was automated in 1963, the year the prison closed. On your way back down to the dock, look along the terraces for the gardens. Army families planted them, then the families of prison staff, and when volunteers cleared decades of overgrowth, they found roses still growing exactly where they had been planted more than a hundred years before.