Police say they are becoming increasingly concerned for the safety of Duncan Burgess, 50, who has gone missing in the Yorkshire Dales.
He was last seen late on Wednesday night at the Old Hill Inn in Chapel-le-Dale near Ingleton.
Duncan has no access to a vehicle or money but is physically fit and can walk long distances.
He may also be living rough, plice say.
A spokeswoman added: “We are particularly appealing to walkers and campers who might have seen him on their travels, including anyone doing the Yorkshire Three Peaks challenge, and to anyone who may have given a lift to Duncan or offered him accommodation in the Yorkshire Dales, Cumbria and Lancashire borders area.”
Duncan is described as white with short, dark, brown hair, brown eyes and is of stocky build.
He was last seen wearing a red fleece, a blue jacket, dark coloured trousers, a tweed cap and was carrying a large rucksack.
Anyone who has seen Duncan or knows where he is now, is urged to call North Yorkshire Police on 101 and pass information to the Force Control Room.
Please quote reference number 12180096352.
