Place · United States

The history of San Francisco

A Civil War fort turned federal prison
Last reviewed 16 October 2026 · A three-minute read · 1775–1986

This record gathers one piece of ground in San Francisco: Alcatraz Island, a rocky point in the bay named by Spanish explorers for its pelicans, built up as a United States Army fort, turned federal penitentiary, occupied by Native American activists, and now kept as a national park.

The short answer

Alcatraz Island in San Francisco Bay began as a Spanish-named rock, became a United States Army fort finished in 1859, served as a military and later federal penitentiary until 1963, was occupied by Native American activists from 1969 to 1971, and has operated as a national park since 1973.

1775 to 1859

A pelican island becomes a fortified army prison

Alcatraz Island is a small island in San Francisco Bay, now preserved as a national park and museum. Spanish naval officer Juan Manuel de Ayala charted the bay in 1775 and named a nearby island "La Isla de los Alcatraces," meaning the Island of the Pelicans. The name later stuck to this rock instead.

In 1846, acting military governor John C. Fremont bought the island for the United States government, paying Francis Temple $5,000. The government later refused to honor the deal, and Fremont spent decades suing for payment he never received.

President Millard Fillmore set the island aside for military use in 1850. The Army Corps of Engineers began building a fort here in 1853 under Lieutenant Zealous B. Tower. Workers finished Fort Alcatraz in 1859, giving the bay a three-story citadel, gun batteries, and a fortified guardhouse. That same year, Captain Joseph Stewart arrived with 86 men. Within months his soldiers locked eleven of their own in the guardhouse basement for desertion, theft, and drunkenness. It was the start of Alcatraz as a prison, years before any civilian criminal set foot here.

1861 to 1898

Confederate, Modoc and Hopi prisoners held on the rock

When the Civil War began in 1861, Alcatraz held Confederate sympathizers and political prisoners under suspended habeas corpus. In 1863, soldiers here arrested the crew of the J. M. Chapman, a Confederate privateer caught trying to slip out of the bay.

The prison kept growing after the war. In 1873, Paiute Tom became the first Native American held on the island. That same year, two Modoc men, Barncho and Sloluck, arrived after being sentenced to hang for killing peace commissioners during the Modoc Wars. Their sentences were commuted to life on the rock instead.

In 1895, the Army imprisoned nineteen Hopi men from Orayvi, Arizona, for refusing to send their children to government boarding schools. They were sentenced to hard labor and released that September, on condition they stop resisting federal policy.

1906 to 1912

The army builds the concrete cellhouse that still stands

The 1906 earthquake cracked the rock on Alcatraz but left its buildings standing. Major Reuben Turner designed a massive concrete cellhouse, finished in 1912, with 600 cells, a kitchen, a hospital, and offices. By 1907, the Army had dropped the name Fort Alcatraz altogether, calling it the Pacific Branch of the United States Military Prison instead.

1934 to 1963

The island becomes a federal penitentiary for hard cases

In 1934, the Justice Department took over the island and turned it into the Alcatraz Federal Penitentiary, a maximum-security prison meant to hold the country's hardest cases. Cold water and fast currents around the island convinced officials no one could swim away from it. The prison closed on March 21, 1963, after 29 years.

1969 to 1971

Native American activists occupy the island for nineteen months

On November 20, 1969, 89 Native American activists landed on the closed prison island. Richard Oakes, a Mohawk organizer, led the group, which called itself Indians of All Tribes. The group claimed Alcatraz under the 1868 Fort Laramie Treaty, which returned unused federal land to Native nations. The group wrote the "Proclamation to the Great White Father and All His People," laying out their demands for Native American sovereignty. Oakes had also offered, half in earnest, to buy the island from the government outright.

The occupation lasted 19 months. Federal agents finally removed the last 15 occupiers on June 11, 1971, ending the longest Native American occupation of federal land in the country's history.

1972 to now

The island opens to the public as a park

In 1972, President Richard Nixon signed the law creating the Golden Gate National Recreation Area, folding Alcatraz into the new park system. The island opened to the public in October 1973. In 1986, it was named a National Historic Landmark.

Today, more than 1.4 million people visit Alcatraz Island every year. Visitors walk the same cellhouse corridors where federal inmates once lived, see the ruins of the warden's house, and look out from the island's lighthouse, the oldest operating one on the West Coast.

Alcatraz Island today is a National Park Service museum, reached by ferry from Pier 33.

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Where this is

37.829°N 122.426°W TILE ≈ 1.2 × 0.6 KM
Place
Alcatraz Island
Town
San Francisco
Country
United States
Tile
≈1.2 × 0.6 km (geohash6)
Last reviewed
16 October 2026

The layers, in order

Sourced records, high and medium confidence. Era background is marked as such.
Early modern
Alcatraz Island
In 1775 Juan Manuel de Ayala charted San Francisco Bay and named the island 'La Isla de los Alcatraces,' the island of the pelicans.
Parks Conservancy · record, high
Modern
Alcatraz Island
Mexican governor Pio Pico gave the island to Julian (William) Workman in 1846, but John C. Fremont bought it for the United States for $5,000 the same year, and Fremont was never paid.
Fort Alcatraz
The U.S. Army Corps of Engineers, under Lt. Zealous B. Tower, built Fort Alcatraz between 1853 and 1859 with a citadel and gun batteries.
Alcatraz Island Lighthouse
The Alcatraz lighthouse, completed in 1854, was the first operating lighthouse on the entire U.S. West Coast.
Alcatraz Island
In 1857 a 7,000-cubic-yard landslide during roadway excavation between the wharf and the guardhouse killed two workers.
Legends of America · record, medium
Alcatraz Island
In 1859 Captain Joseph Stewart confined eleven soldiers in the guardhouse basement for desertion, theft and drunkenness, starting Alcatraz's long run as a military prison.
Fort Alcatraz
Alcatraz became a detention site for Confederate sympathizers and privateers, including the seized crew of the J.M. Chapman in 1863.
Parks Conservancy · record, high
Alcatraz Island
Modoc men Barncho and Sloluck were sent to Alcatraz in 1873 after a death sentence for killing peace commissioners, and in 1895 nineteen Hopi men from Arizona were imprisoned for resisting government land and schooling policy.
Main Cellhouse
Between 1906 and 1912 the Army built the large reinforced concrete cellhouse that still stands, with 600 cells, a hospital and a dining hall.
NPS History · record, high
Alcatraz Island
In 1934 the island became Alcatraz Federal Penitentiary, built to hold the prisoners other prisons could not control.
Alcatraz Island
Bernard Coy, Joseph Cretzer and Marvin Hubbard's breakout attempt in May 1946, the 'Battle of Alcatraz,' left Coy and Cretzer dead on the island.
Wikidata · record, high
Alcatraz Federal Penitentiary
In June 1962 Frank Morris and the Anglin brothers slipped through hand-dug holes behind their cells and vanished into the bay on a raft, never confirmed dead or alive.
Alcatraz Federal Penitentiary
Alcatraz Federal Penitentiary closed on March 21, 1963, after the cost of running an island prison became too high.
Alcatraz Island
On November 20, 1969, 89 Native American activists led by Richard Oakes landed and occupied Alcatraz for nineteen months, demanding the island under the Treaty of Fort Laramie, until federal agents removed the last occupiers on June 11, 1971.
Alcatraz Island
Alcatraz opened to visitors in October 1973 after the Golden Gate National Recreation Area was created by law in 1972, and now draws roughly 1.4 million visitors a year.
Parks Conservancy · record, high
Alcatraz Island
Alcatraz Island was listed on the National Register of Historic Places in 1976 and designated a National Historic Landmark in 1986.
Wikidata · record, high

Questions about this place

Answered in one sentence, then in full above
What was here before Alcatraz Federal Penitentiary?
Before the federal penitentiary opened in 1934, Alcatraz was a United States Army fort and military prison, built between 1853 and 1859 and later rebuilt with a large concrete cellhouse finished in 1912.
Why is Alcatraz Island called Alcatraz?
Spanish naval officer Juan Manuel de Ayala charted San Francisco Bay in 1775 and named a nearby island 'La Isla de los Alcatraces,' meaning the Island of the Pelicans; the name later stuck to this island instead.
What happened during the occupation of Alcatraz?
On November 20, 1969, 89 Native American activists led by Richard Oakes landed on the closed prison island and occupied it for nineteen months, claiming it under the 1868 Fort Laramie Treaty, until federal agents removed the last occupiers on June 11, 1971.
When did Alcatraz prison close?
Alcatraz Federal Penitentiary closed on March 21, 1963, after 29 years of operation as a maximum-security federal prison.
Is Alcatraz Island open to the public?
Yes, Alcatraz Island opened to visitors in October 1973 after being folded into the Golden Gate National Recreation Area, and it now draws more than 1.4 million visitors a year.

Where this came from

1
Wikipedia - Alcatraz Federal Penitentiary — Alcatraz becomes a federal penitentiary
2
Wikipedia - Alcatraz Island — The island was granted away, then seized by the army
3
GSA / Wikipedia - Fort Alcatraz — Fort Alcatraz built to guard the bay
4
Legends of America — A landslide killed two laborers
5
Wikipedia - Alcatraz Island Lighthouse — The West Coast's first lighthouse lit here
6
National Park Service - Alcatraz Military Timeline — Military prisoners held from 1859
7
Parks Conservancy — Confederate prisoners held during the Civil War
8
Colorado State University History / Legends of America — Modoc and Hopi prisoners held here
9
NPS History — The concrete cellhouse goes up
10
Wikidata — Prisoners who died in the escape attempt of 1946
11
Wikipedia - June 1962 Alcatraz escape — The 1962 escape through the air vents
12
Wikipedia - Occupation of Alcatraz — Native American activists occupy the island for 19 months
13
Wikidata — Made a National Historic Landmark

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