Kolkata Metro Special Cover --- This Special Cover was issued by IndiaPost on 20th November 2015 during a Philatelic exhibtion on Metro Railway, at Esplanade Metro Station Kolkata, on the occasion of 31 glorious years of service of Metro Railway, Kolkata since 1984. As in the picture, the special cover includes a cover depicting the occasion along with a cancelled stamp of 150 yrs of Kanchrapara RWS. The Cover costs ₹ 15/- each.