The Waterloo & City and the Jubilee were the coolest lines, while the Metropolitan and Hammersmith & City attracted fewest complaints. TfL said air-conditioned trains were in use on 40 per cent of the Underground network. New trains due to be introduced on the Piccadilly line from 2025 will also have air conditioning.
VictoriaThe Victoria Line is teeming with bacteria, having the highest number of germs of all the Tube lines. Touching your face after coming into contact with dirty seats and handles can transfer a whole host of blemish-causing bacteria.