A City's End, Written and Unearthed
In 1620 CE, a powerful earthquake erased the city of Akhsiket from the map. Once a thriving capital of the Fergana Valley on the Silk Road, the city was completely destroyed, and its inhabitants relocated to what is now Namangan. For centuries, the primary record of this event came from a chronicle titled "Ajoyib at-tabaqat" ("Wonders of the Regions"), written in 1640 by Sayyid Muhammad Tahir ibn Abdul Qasim. He described the event firsthand, noting that buildings were destroyed, trees were uprooted, and many people were trapped under the collapsed structures. The earthquake was so localized and intense that the fortress of Akhsiket experienced the strongest shaking, while villages just 8 kilometers away felt much weaker tremors.
The city of Akhsiket was an important center long before its destruction. Established as early as the 3rd century BCE, it grew into a major fortified city covering 30 hectares. By the 10th century, it was the capital of the Fergana Valley, containing a palace, a prison, mosques, and a large caravanserai, all protected by extensive defensive walls. The father of the Mughal Emperor Babur, Umar Shaikh Mirza II, ruled from Akhsiket in the 15th century. The city was also a known production center for high-quality Damascus steel, with archaeologists discovering fire-resistant crucibles capable of withstanding the 1,300 degrees Celsius temperatures needed for the process.
Where Geology and History Converge
The historical account of Akhsiket's demise provides a rare opportunity for archaeoseismology, a field that combines archaeology and geology to study past earthquakes. Scientists investigating the region's fault lines discovered physical proof that corroborates the written history. By digging a trench across a fault that runs directly through the ancient city, geologists exposed deformed and offset layers of sediment, showing a surface-rupturing earthquake. This investigation is a core method of paleoseismology, using geological records to understand seismic events that occurred before modern instruments existed.
Analysis of the trench revealed a seismic event with a magnitude estimated at M=7.6. The displacement seen in the rock layers corresponds to a massive release of energy that would have destroyed the mud-brick structures common in the city. Archaeological excavations have uncovered human remains amid the ruins of collapsed buildings, providing a grim tally of the disaster's victims. The convergence of the written chronicle, the archaeological body count, and the geological evidence from the fault trench creates a detailed picture of a specific catastrophic event from over 400 years ago.