tube surfing

tube surfing

Sports medicine
A variation of the adrenaline “sport” train surfing, in which an unknown number of thrill seekers ride on the roofs of the London Underground, which has resulted in an unquantified loss of life and limb.
 
Vox populi
A banal activity in which a rider of the London Underground tries to stay afoot while the train is in motion without hanging on to the straps, poles or other fixed parts of the carriage.