Archaeologists in Patna have unearthed a series of massive sal-wood timber palisades dating back to the Mauryan Empire (3rd century BCE). These wooden walls, mentioned in the accounts of the Greek ambassador Megasthenes, were designed to protect the imperial capital of Pataliputra from floods and invaders. The wood remains remarkably preserved due to the anaerobic conditions of the riverine silt.
The excavation provides physical confirmation of ancient Indian urban defense strategies described in Kautilya's Arthashastra. These timbers showcase an advanced joinery technique that allowed the structures to withstand the pressure of the Ganges river for centuries.