Derbyshire police say they are very concerned for the safety of 76-year-old William (Billy) Burns who is missing from his home in Hadfield.
He was last seen at 8.35 this morning at Hadfield railway station getting a train to Ashburys in Manchester which arrived at about 9.12.
It is not known if Mr Burns, who suffers from dementia, got off the train at one of the eight stops in between to the two stations or at Astburys.
He is 5ft8in tall, with curly grey hair. He was wearing a blue anorak, grey trousers and black shoes and carrying a walking stick.
Contact the police on 101, quoting Derbyshire police incident 264 of February 2.