In this July 7, 2011, file photo, Jim Breeden of the Golden Gate National Parks Conservancy, walks through the dungeons below the main cell house during a night tour on Alcatraz Island in San Francisco. (AP Photo/Eric Risberg, File)

Hidden tunnels found below Alcatraz prison

Archaeologists find buildings and tunnels under prison yard at famed San Francisco pen

Archaeologists confirmed a long-time suspicion of historians and say that famed Alcatraz prison was built over a Civil War-era military fortification.

Researchers found a series of buildings and tunnels under the prison yard of Alcatraz Federal Penitentiary, which once held Al Capone, SFGate reported Tuesday.

A study published last week in “Near Surface Geophysics” said archaeologists used ground-penetrating radar and terrestrial laser scans and historical maps and photographs. They found fully buried structures, ammunition magazines and tunnels.

“This really changes the picture of things,” study author Timothy de Smet, an archaeologist at Binghampton University, told PBS. “They weren’t erased from the island — they are right beneath your feet.”

Archaeologists are now planning more study to discover what else lies just below the surface.

READ MORE: B.C. bolsters protections of heritage, archeological sites

Historians believe workers built over existing structures when the prison was built in the 20th century.

Alcatraz first came to the attention of the U.S. government after it took control of California from Mexico in the 1840s. Its location in San Francisco Bay made it attractive for military fortification purposes.

During the Civil War, Fort Alcatraz was the official military prison for the West Coast.

In the 1930s, the first federal prisoners — deemed by the media to be the worst of the worst — began arriving. The last inmate left in 1963.

The Associated Press

Like us on Facebook and follow us on Twitter

Just Posted

Two nature-inspired artists display oil paintings at Qualicum gallery

Judy Maxwell and Lloyd Major depict scenes of wildlife, landscapes and the west coast

Parksville seniors getting stronger with age

Weightlifting couple qualify to compete at Worlds Masters in Montreal in August

Camera captures cougar lurking in Parksville’s Foster Park neighbourhood

Resident shared photo to alert others to big cat’s presence

VIDEO: RCMP ask kids to help name soon-to-be police dogs

13 German shepherd puppies will be born this year

New Zealand leader vows to deny notoriety to mosque gunman

The shooting killed 50 in a Christchurch mosque, and left the country reconsidering gun laws

Air Canada grounds its Boeing Max 8s until at least July 1 to provide certainty

Airlines around the world have been working to redeploy their fleets since their Max 8s were grounded last week

Budget to tout Liberal economic record, provide distraction from SNC furor

This is the Liberal government’s fourth and final budget before the election

Vancouver Island overdue for the big one, can also expect mega-thrust tsunami

The last big earthquake was 70 years ago in Courtenay

Horvat scores 16 seconds into OT as Canucks beat Blackhawks 3-2

Pettersson sets rookie scoring record for Vancouver

Vancouver Island cancer survivor not giving up fight

Kim Angell grows from advocate and blogger to the face of national campaign

No injuries, pollution in Vancouver Harbour ship collision: Transport Canada

Transportation Safety Board says it has deployed a team of investigators look into the incident

Budget 2019: Five things to watch for in the Liberals’ final fiscal blueprint

Finance Minister Bill Morneau will release the Trudeau government’s final budget on Tuesday

Most Read