Oldest Wall of Ostia

This tufa block wall (late 4th–early 3rd c. BC) in Ostia Antica is the oldest surviving structure in the area, showcasing early Roman construction techniques using volcanic stones. Likely part of a fortification or cult site, it marks Ostia’s origins as a military colony guarding the Tiber’s mouth. This wall reflects the strategic importance of Ostia in ancient Rome, highlighting the city's role in protecting vital trade routes and its early urban development.