Halaesa, founded in the late 5th century B.C. on the Tyrrhenian coast of Sicily, was an important city in the Hellenistic and early imperial periods. Declining in the middle imperial period, it later became a diocese until it was finally abandoned. From the 1950’s onwards, the Superintendency of Messina and the University of Messina undertook numerous excavation campaigns (agora, houses, roads, necropolis, fortifications). More recently (from 2016), investigations have been undertaken by the Universities of Amiens (theatre, acropolises), Messina and Oxford (joint excavation of the north sanctuary). In 2020, the University of Palermo (in association with the Archaeological Park of Tindari) began a project in the north-eastern sector of the fortifications. The area lays between Towers B and C identified by Gianfilippo Carettoni, who excavated in 1952 and 1954. In the area of the new project, beyond the towers and the curtain wall (a postern gate opened in this section), two structures are visible above ground (never previously documented). The south wall of one of them presented a waterproof layer of _opus_ _signinum_, suggesting that it may be part of a cistern. The aim is to identify the construction and occupation phases both of the fortifications and the probable cistern, and the relationship between the fortifications and the road network. The 2020 and 2021 excavations identified at least two phases, datable to the late Hellenistic and early imperial periods: the cistern had been repaired and the fortifications had two distinct defensive lines, and between the late 2nd and the 1st century B.C. the postern gate was blocked, perhaps at a time when the city was in danger. A geophysical survey in the area of the cistern seems to indicate the presence of buried structures.