Alcatraz Island was named Isla de los Alcatraces or “Island of the Sea Birds” in 1775, by Spanish lieutenant Juan Manuel Ayala when the Spanish first entered San Francisco’s harbor. Although the Spanish sailed into the area in the late 18th century, San Francisco was considered a small, unimportant city until the mid-19th century, after the United States bought California from Mexico just prior to the Gold Rush. Around this time the population of San Francisco went from about 500 to 35,000 people in a span of just three years. This was the first time officials found themselves needing to protect this region of the California coastline from outsiders, so a fort with hidden armament tunnels beneath was built on the once secret Alcatraz.
Although the army once came close, in the end, not one shot ever needed to be fired from Alcatraz Island, which housed the biggest fort west of the Mississippi during the American Civil War. The state found a need for a place to keep prisoners, and the fort at Alcatraz was used. The tunnels were bomb proof and were covered in earth, and would have been used to ferry men and ammunition in and out. Also partially buried was a structure called a caponier, a building that jutted out of the rock itself, into the bay, and was used to provide defensive cover. Once the civil war was over, the fort was used periodically to house other groups, namely Spanish Philippine P.O.W.s during the Philippine-American War, and during WWI, conscientious objectors. Things were quiet in California for a while, until the American government found they needed to use Alcatraz, but not its tunnels, to house mobsters like Al Capone who had created a hidden crime syndicate right beneath the country’s very nose. The fort was largely demolished and a federal penitentiary was built-in its place. It was assumed ever since that the underground portion of the fort had disappeared in the demolition and reconstruction.
Recently, researchers from Texas A & M University went to Alcatraz at the request of the National Park Service to try to locate Civil-War-era structures. Using a hand-held, one-wheeled device that looks like a surveyor’s distance-measuring tool, ground-penetrating radar was used to essentially bounce sound off of underground structures and objects, creating an image much the way that medical imaging maps the interior of a body. While in California, researchers found that not only were the tunnels largely not destroyed, they had been hidden beneath Alcatraz prison for almost a century with, it looks like, at least one magazine building and the caponier. Everyone is very excited by the find, and if it turns out that the caponier in particular is indeed intact, archaeologists will soon begin excavation to try to unearth access to the tunnels for future touristic visits. As for the rest of what is underneath, geophysical studies can attempt to learn much of the contents without overly disrupting the site, as the humid salt air could rapidly damage what has so long been protected.
By Julie Mahfood