When you stop to think about it, the designs of London's transport network are some of the most enduring symbols of the city. The red bus or black cab are as much a part of the shorthand for London as a shot of the Palace of Westminster or the Thames.
Now TfL is on the hunt for the public's favourite transport icon. A panel made up of industry experts, TfL and London Transport Museum staff has already selected a shortlist of 100 for people to pick from.
There's a selection in the gallery below to get you thinking about your favourites — see them all on the website. Currently the top-ranking items are (predictably) the black cab, Harry Beck's original Tube Map, and the TfL roundel. You can make a difference by voting for your favourites before the deadline of 1 October.
The winner will be announced on 15 October. TfL's hunt for London's best transport design icon is part of an 18-month celebration called Transported by Design, which will include events, competitions and exhibitions across London.