Siemens Mobility is currently conducting testing on the upcoming Piccadilly line trains, employing both the test track and a climate chamber in Germany and Austria. These new trains are slated to commence passenger service in London from 2025, marking the replacement of the current fleet from the 1970s. The Piccadilly line, integral to the London Underground with a ridership share exceeding 10 per cent, serves key destinations including Heathrow Airport, the West End, and St Pancras International.