Laser Scans Detect Hidden Buildings and Tunnels Beneath Alcatraz Prison

iStock.com/f8grapher
iStock.com/f8grapher

Isolated in the San Francisco Bay and surrounded by steep cliff faces, Alcatraz Federal Penitentiary seemed like the most secure place to keep dangerous criminals in the mid-20th century. But it's recently come to light that every inmate on Alcatraz Island lived above a series of potential escape routes that predated the prison's construction, the San Francisco Chronicle reports.

In a new study published in the journal Near Surface Geophysics, archaeologists reported their discovery of structures and artifacts beneath the Alcatraz prison yard, including underground buildings, tunnels, and ammunition magazines. Guided by historical maps, documents, and photographs, they used laser scanning technology and ground-penetrating radar to locate the subterranean fortress close to the surface.

The site dates back to the mid-19th century, when Alcatraz Island was used for military purposes. The same natural features that would later make Alcatraz an appealing prison also made it an ideal coastal fortification. Enough brick buildings were built there to house 200 soldiers and enough food was shipped in to feed them for four months.

But the fortification wasn't used for its original purpose for very long. It was transformed into the West Coast's official military prison during the Civil War, and in the 1930s, the government turned it into a federal prison. Instead of tearing down the forts and tunnels leftover from its military days, workers left them intact and built over them to save money. Archaeologists plan to investigate the underground structures further without disturbing the historic site.

Alcatraz Prison closed in 1963, so the underground tunnels no longer pose a security problem. Today the island is part of the U.S. National Park Service and is a popular tourist attraction.

[h/t San Fransisco Chronicle]

The Site Where Julius Caesar Was Assassinated Will Open to the Public in 2021

iStock.com/Largo di Torre Argentina
iStock.com/Largo di Torre Argentina

Besides being a sanctuary for stray cats, Largo di Torre Argentina in Rome is best known as the place where Julius Caesar was stabbed 22 times by assassins in 44 BCE. As the city's oldest open-air square, the spot is an important piece of Roman history, but it's fallen into disrepair. Now, Condé Nast Traveler reports that Largo di Torre Argentina will reopen to the public following a $1.1 million restoration project.

The site includes four ancient temples, a medieval brick tower, and the ruins of the senate house where Caesar was murdered. About 20 feet below street level, it was excavated under the rule of Benito Mussolini in the 1920s, and has remained largely closed to the public since. Today, Largo di Torre Argentina is overgrown and accessible only to the feral cats that live there.

On Monday, February 25, Rome mayor Virginia Raggi announced that Largo di Torre Argentina will reopen in the second half of 2021. To get the site ready for the public, the city will add restrooms, install lights, and build walkways that allow visitors to explore the area. Stone ruins, some of which are stacked into piles, will be secured, and artifacts currently sitting in storage will be moved to a museum. The one area the project will avoid is the corner where the cat sanctuary is located.

Rome, of course, is filled with ancient ruins—some that residents weren't even aware of until recently. In 2014, a 2000-year-old Roman road was unearthed during the construction of a McDonald's.

[h/t Condé Nast Traveler]

Scientists Solve an Ancient Stonehenge Mystery: Where the Massive Rocks Came From

iStock.com/Onfokus
iStock.com/Onfokus

It's one of the greatest archaeological mysteries of all time: How did Neolithic peoples build Stonehenge—a massive, bluestone structure in an area where no stones of that kind can be found? As CNN reports, a new study answers some of the questions the site raises and puts other theories to rest.

The first stage of Stonehenge, located in what's now Salisbury, England, was built roughly 4000 years ago. Archaeologists have known for a while that the bluestones used to make Stonehenge originated from quarries in Pembrokeshire, Wales, 150 miles away, but how the stones arrived at their current spot is less clear. According to one theory, humans spent months transporting the materials, possibly with wooden sleighs on rollers, oxen, or river rafts.

Other experts insist that it would have been impossible to transport the 25-ton rocks such a great distance using primitive technology. Instead, they say the stones were placed there by glacial activity.

The new study published in the journal Antiquity debunks that idea. Archaeologists and geologists from the UK studied the smaller rocks used to build Stonehenge and pegged them to two quarries in the Preseli Hills of Wales. Upon visiting the sites, they discovered traces of tools, stone wedges, and digging activity. The evidence dates back to 3000 BCE, the same time when construction on Stonehenge started.

The results also dispel previously held beliefs concerning the rocks' origins. Though it's widely accepted that the stones came from the Preseli Hills, this study is the first to trace them to two specific quarries on the north side of the hills—Carn Goedog and Craig Rhos-y-felin. It was thought for nearly a century that the rocks were excavated from the opposite side.

The research team says their findings suggest that materials used to make Stonehenge were moved by purposeful human activity rather than freak natural forces. But the study still leaves some questions unanswered, such as how the ancient peoples were able to transport the rocks 150 miles after digging them up. The fact that the rocks came from the north side of the Preseli Hills suggests they were dragged over land rather than transported by river—though the exact methods used remain a mystery .

[h/t CNN]

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