The InterCity 125s were introduced into passenger service from 1976 and instantly revolutionised rail travel. As the world’s fastest diesel train they heralded significant journey time reductions, reversing declining demand without requiring the construction of new lines to accommodate them. At each end of the train a sleek 2,250hp power car with its iconic nose cone shape made the 125 an instantly recognisable train while the distinctive noise produced by the original turbocharger resulted in a train that commanded attention wherever it went. A fleet of 197 power cars was built, enabling them to provide the mainstay of many InterCity routes. Between each power car a rake of Mk 3 carriages delivered passenger comfort that was still to be beaten more than forty years later. Privatisation saw the 125’s refurbished and repainted as they remained at the forefront of their new owners fleets. I has resulted in an array of different liveries, internal refurbishments and changes to operational duties, while the installation of new engines has enabled continued operation well into the twenty-first century.With an array of fascinating photographs and insights, the 125 Group tells the story of an enduring icon of Britain’s railways.