Researchers have unveiled Itiner-e, the most detailed open digital dataset of Roman roads ever assembled, covering nearly 4 million km² and nearly doubling previously known road lengths. The dataset reveals only 2.737% of road locations are known with certainty, highlighting significant archaeological unknowns while enabling transformative studies of ancient mobility, trade, and infrastructure evolution. This resource integrates historical sources, modern topography, and remote sensing with segment-level metadata, providing a critical foundation for analyzing connectivity and empire dynamics.