The largest earthquakes in Saudi Arabia occur on transform faults, such as in the Gulf of Aqaba where a magnitude 7.3 earthquake struck in 1995. The Red Sea rift is composed of several offset ridge segments that likely are separated by transform faults, leading to significant seismic hazard at the nearby coastlines. One of the largest rift offsets (~100 km) is located in the northern Red Sea at latitudes 23N–26N and is usually referred to as the Zabargad Fracture Zone (ZFZ). This area is also the location of the most intensive seismic activity of the northern Red Sea. Historical and national earthquake catalogues report two earthquakes of magnitude larger than 6 within the ZFZ, indicating the potential for future large earthquakes in the area. The ZFZ extends from Zabargad Island in the south (near the Egypt/Sudan border) to the Al Wajh platform in the north on the Saudi side. Large earthquakes within the ZFZ would threaten neighboring coastal communities on both sides of the Red Sea, in particular on the more populated Saudi coast, e.g., the city of Yanbu with its large petrochemical facilities, the town of Umm Lujj, and a new major tourist resort in development (The Red Sea Project).Despite previous geophysical investigations focusing on rift extension, sedimentary cover, and transform fault formation, the structure and seismicity of the ZFZ remain poorly known due to thick salt deposits and incomplete seismological datasets. To overcome these limitations, we conducted the first passive seismic deployment in the Red Sea, specifically targeting the ZFZ. The ZAFRAN (Structure and earthquake potential of the Zabargad Fracture Zone, northern Red Sea) network comprised 14 ocean-bottom seismometers, 12 from German Instrument Pool of Amphibian Seismology (DEPAS) and 2 from a Fugro experiment, and four portable onshore broadband seismic stations from KAUST, installed on islands and along the Saudi coast. This dataset enables high-resolution observations of earthquakes occurring within the ZFZ and provides improved event locations and focal mechanisms.Together with offshore seafloor imaging, sub-bottom profiling, magnetic surveys, and the re-analysis of existing geophysical data, the OBS network forms the backbone of a new interdisciplinary approach. By combining these observations with analogue models of transform faults and salt tectonics, we aim to develop a conceptual model of the ZFZ evolution and to better constrain its seismic and volcanic hazard potential for the surrounding Red Sea region.