Carl was one of the last four ponies to leave the UK mining industry in 1994, when pit ponies were replaced by modern mining machinery at Ellington Colliery, Northumberland.

Carl retired to the National Coal Mining Museum near Wakefield, West Yorkshire and died in early October at the age of 29, leaving lifelong friend Sparky as possibly the last surviving deep mine pony.

Carl was a working pony even in retirement: during his time at the museum he participated in and attended many local shows and events, allowing people to learn how pit ponies lived and worked.

“Carl was a wonderful pony, full of character and very mischievous; we know Carl will be sorely missed as he was loved by all who met him,” a museum spokesperson said.

“His loss will be felt by all the staff at the museum, the visitors and those who adopted him.”

Pit ponies were once integral to the coal industry, often spending months underground hauling heavy carts of coal to the surface and towing heavy girders from inaccessible reserves.

More than 70,000 were used in collieries at the turn of the last century, but numbers dwindled as ponies were replaced by modern equipment in the early 1990s.

Carl and Sparky were among the last ponies to emerge from the country's coal mines 12 years ago, ending a 300-year-old tradition.