At least 36 trains were delayed and 17 trains rescheduled on Sunday due to dense fog in most parts of north India, a railway official said.
According to the Northern Railway official, the Howrah - Lal Kuan Express was running over 14 hours behind its schedule, the North East Express was running 14 hours late and the Sealdah - Amritsar Jalianwala Bagh Express was over nine hours late.
The official also said that at least 17 trains were reschudeled.
Meanwhile, according to the Delhi International Airport Limited, which manages operations at the Indira Gandhi International airport here, no flight was cancelled on Saturday.