Metropolitan Railway A class 4-4-0T steam locomotive No. 23

This steam locomotive was extensively used on the Metropolitan and Metropolitan District railways for over 80 years. It is one of the original A-class locomotives that pioneered the early development of London's Underground trains. From 1935 to 1948, it was used for track maintenance duties and at the time became Britain's oldest working steam locomotive. At the turn of the century, the Inner Circle line was jointly owned and managed by the Metropolitan Railway. This locomotive was used for services on the Inner Circle until the line was converted to electric in 1905.