In the 2nd century CE, Romans built a mysterious structure near the Colosseum decorated with sea creatures. Nearly 2,000 years later, its mosaic offered a surprising clue that it may have housed Rome's firefighters

For nearly 2,000 years, a Roman building near the Colosseum kept its real purpose hidden. Its walls carried elaborate decoration, while a striking mosaic showed a dolphin, fish, lobster and crab. At first, such luxury could suggest the home of a wealthy Roman. Now, archaeologists are considering another possibility. The building may have housed the vigiles , ancient Rome’s organized firefighters and night watchmen. The evidence is not conclusive. Yet the marine mosaic closely resembles decoration found at a known firefighters’ barracks in Ostia, giving researchers a surprising new clue about life in imperial Rome.

What was the mysterious Roman building near the Colosseum?