A publication of the Archaeological Institute of America
Thousands of planes leave Venice's Marco Polo Airport every year, flying north over corn and soybean fields before turning out over the Adriatic Sea. But until a University of Padua geology team combined aerial photographs, satellite images, and a digital terrain model of the area seven miles from the airport, no one had seen Altinum, an ancient Roman city that lies only five feet below the surface. Altinum is one of very few Roman cities in Europe, and the only one in northern Italy that was not built over after it was abandoned in the seventh century A.D.
Project leader Andrea Ninfo used visible light and near-infrared aerial photos that highlight subsurface architectural elements such as walls, foundations, and even canals. "I found it very hard to get to sleep on the day I realized how much information we could use from these images," says Ninfo. His team produced the first plan of Altinum, a city of about 20,000 and an important harbor on the Roman trade network between the first and the fifth century A.D. Altinum is the possible starting point of the Via Claudia Augusta, a major road built primarily in the mid-first century A.D. to link the Po River Valley and the province of Rhaetia (modern Austria), and to transport goods to the empire's far north and northeastern boundaries on the Danube.
The discovery that a canal system once ran throughout the city is tantalizing evidence that Altinum's residents--forced to flee between the fifth and the seventh century A.D. because of repeated barbarian invasions--already had experience creating a habitable city in a marshy lagoon when they settled the nearby islands that would become Venice.
The mapping effort is part of a larger study of the Via Annia, a road built in 131 B.C. to cross the region (later province) of Cisalpine Gaul. Scholars have known the location of Altinum from literary sources, including the geographer Strabo (64/63 B.C.- A.D. 24) who placed it in the marshes around the Lagoon of Venice. But the removal of the ancient city's building materials to create the churches and palaces of small island communities near Venice have made it impossible to imagine what Altinum actually looked like. Ninfo's team has not only created a city plan, but also mapped the city walls and gates, theater, odeon (a small theater where music and poetry competitions were held), forum, shops, and houses--typical features of thriving cities across the Roman world and testaments to Altinum's prosperity. With the detailed map in hand, the team hopes to identify promising targets for future excavation.