The Marathas never came, but Kolkata dug a ditch anyway — where to find it now

In 1742, fear of Maratha raids prompted the British and locals in Calcutta to dig a three-mile defensive trench. Though never attacked, the Maratha Ditch became a city boundary, later filled to create roads. Today, its trace survives in street layouts and a lane named Maratha Ditch Lane in Baghbazar.