Construction on Rome's Metro Line C has turned up a treasure trove's worth of ancient artifacts, and Phys.org reports that Roman barracks dating back to the second century are the latest find to be unearthed by the project.

The 39-room barracks, which once housed Roman Praetorian guards during the period of Emperor Hadrian, cover 9600 square feet. They were discovered by an archaeologist 30 feet below street level as construction workers nearby poured concrete for the city's upcoming Amba Aradam metro stop. It's one of five barracks that have been identified in the area, which means the location likely once served as a military neighborhood. The new site also contains a mass grave where the remains of 13 adults have been uncovered.

This most recent discovery is one of many that have been stumbled upon since work on Rome's third Metro line began in 2007. In 2009 construction was stalled following the discovery of Emperor Hadrian's "Athenaeum," and in 2014 archaeologists excavated the largest Roman water basin ever found. The new metro stop is set to open in 2020, and officials say they're planning to integrate this newest discovery into the station.

[h/t Phys.org]

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