This means we’ve underestimated the total length of the empire’s routes by more than 62,100 miles—almost doubling previous mapping efforts. The latest updated maps now indicate Rome’s roads covered over 1.5 million square miles. The database currently includes 14,769 road sections, with nearly 63,400 miles of main routes and about another 121,600 miles of secondary roads. Meanwhile, even fewer actual roads remain discernible in the modern landscape. The researchers also note that the map illustrates a single moment in the Roman Empire’s more than 500 years of existence.