The drain is paved with stones in the bottom and its arch is constructed with lakhori bricks.
A lakhori brick lined late Mughal-era drain was unearthed in front of Delhi Gate of the Red Fort by the Archaeological Survey of India (ASI) around two weeks ago.
The structure will soon be ready for reuse.
“The drain runs for around 30 metres and connects the Delhi Gate with the moat surrounding the Red Fort. It was found about two-and-half feet below the surface,” an official from the ASI said.