Archaeological excavations and surveys were undertaken on the submerged structures identified during research campaigns in 2005-2006-2007 in the area of the submerged road on the island of Mozia. Mozia is the site of one of the Mediterranean’s best known Phoenician-Punic colonies, and without doubt its so-called ”submerged road” is unique in the archaeological world. In fact, the road following a more or less straight line towards the north links the North Gate of the town walls to the coast in front of it, near the contrada Birgi, crossing the northern tract of the Stagnone di Marsala (Marsala Marshes). Recent archaeological investigations revealed that the road was built on an artificial embankment or earthwork. During the life of the Phoenician-Punic colony the road surface, now underwater, must have been above the sea level of that period, which still cannot be precisely calculated. Moreover, at circa 160 m from the North Gate, flanking the road to the east, part of a quay was identified and excavated. This seemed to have been part of the system for closing and defending the Stagnone near the North Gate and the island’s necropolis which is clearly visible in aerial photographs. The excavation, underwater survey, interpretation of the aerial photographs and the use of new technology have contributed to the beginning of a research programme that is of fundamental importance for the reconstruction of port activity at Mozia.