1973 Stock

The London Underground 1973 Stock is a type of rolling stock used on the Piccadilly line of the London Underground. It was introduced into service in 1975 with the extension of the line to Hatton Cross in 1975, followed by a further extension to Heathrow Central in 1977.

The trains were built by Metro Cammell between 1974 and 1977, and were refurbished by Bombardier Transportation between 1995 and 2000. They are the one of the oldest remaining tube trains, in service for 43 years, the other one being the 1972 Stock running on the Bakerloo line. Along with the 1992 Stock and 1972 Stock, the 1973 stock is due to be replaced by the New tube for London.