SOUTHAMPTON, ENGLAND—Ostia, a port of ancient Rome, extended beyond the Tiber River, which had been thought to form the northern edge of the city. Researchers from the University of Southampton and the University of Cambridge discovered a new section of the city’s boundary wall on the opposite side of the Tiber while conducting a geophysical survey of the region between Ostia and Portus, another Roman port. They say that the newly discovered area contained three huge warehouses. “Our research not only increases the known area of the ancient city, but it also shows that the Tiber bisected Ostia, rather than defining its northern side,” Simon Keay, director of the Portus Project, told The Telegraph.