The Herat Fault is a major east-west lineament stretching across central and western Afghanistan, one of the longest and most prominent faults in the country. It runs along the southern edge of the Hindu Kush and marks an ancient tectonic suture that has been reactivated as Arabia and India drive northward into Eurasia, producing largely strike-slip motion.
Although parts of the fault have been comparatively quiet in the instrumental era, it lies within a broadly deforming region where thrust and strike-slip faults interact. Poor building construction and remote mountainous terrain make Afghan communities along and near the fault highly vulnerable when earthquakes do strike.
The wider Herat region suffered a catastrophic earthquake sequence in October 2023, when a series of magnitude-6.3 shocks devastated villages west of the city of Herat and killed thousands of people. These events, together with the fault's great length and slow strain accumulation, keep the Herat Fault firmly on the list of significant seismic hazards in the Middle East and Central Asia.