BINGHAMTON, NY - High-tech radar and laser scans have uncovered a hidden military traverse underneath the infamous Alcatraz penitentiary, according to research led by faculty at Binghamton University, State University of New York.

Binghamton University archaeologist Timothy de Smet and colleagues used terrestrial laser scans, ground-penetrating radar data and georectifications (the process of taking old digitized maps and linking them to a coordinate system so that they can be accurately geolocated in 3D space) to locate and assess the historical remains beneath the former recreation yard of the Alcatraz penitentiary.

This unique, nondestructive research method revealed that remnants of buried structures, including a "bombproof" earthwork traverse along with its underlying vaulted brick masonry tunnel and ventilation ducts, ran east to west beneath the recreation yard of the Alcatraz penitentiary.

de Smet said he was shocked to discover that the historical structures were maintained in such good condition.

We also learned that some of the earthwork traverses were covered over with thin concrete layers through time, likely to decrease erosion on the rainy windy island.

It was wonderful to find the history just beneath our feet that we can visualize for the public."

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