London's tube roundel is an internationally recognised symbol of the city. The red, white and blue signs are used at all underground stations, while adapted forms can be found on buses, trains and many other types of transport.
For a standardised bit of signage, the famous tube roundel is surprisingly diverse. Here we take a look at some of the many oddities on the network. Warning: what follows may get a bit geeky.
Maida Vale's glorious mosaic sign is an original design feature of this Grade II listed station. The Bakerloo stop celebrated its 100th birthday last year. When it opened, Maida Vale was entirely staffed by women — a novelty at the time, prompted by changes to the workforce during the first world war.
The District line's West Brompton station has a double peculiarity in its roundels. As shown above, the name bar is framed with a bright blue border. The name itself, meanwhile, looks a little odd — witness the crossed W, and the bottom-heavy E. It's a vintage sign that still uses the original Johnston typeface, introduced a century ago. Nearly all other signs on the network now use the refreshed New Johnston typeface, designed by Eiichi Kono in 1979.
The three Heathrow stations are the only ones on the network to include numerals — and an aeroplane graphic. As if that were not exciting enough, Heathrow Terminals 1,2,3 is the only station to use a comma (used twice, without spaces). A third oddity is that this roundel now shows an out-of-date name. Terminal 1 closed last year, and is under demolition. The station is now known as Heathrow Terminals 2&3 on the official tube map.
While we're at Heathrow, we might as well show a picture of another rare use of the roundel. This sign was snapped at Heathrow Terminal 2, and gives passengers direction rather than a station name. More common variants include the 'To trains' and 'Way out' roundels, seen at several tube stations.
Harrow on the Hill has a long name. While other wordy tube stations such as High Street Kensington, King's Cross St Pancras and Great Portland Street display their names in one font size, the west London station diminishes its smaller words to give us this mixed-font roundel.
We're not sure if the recessed roundels of Fulham Broadway are unique, but we're rather fond of the effect — as though the sign is imitating a tunnel-boring machine and coring out its own tunnel. (Tube geeks will quickly point out that Fulham Broadway, only a little below ground level, was never excavated in this way.)
This beauty lurks on the stairwell at Aldgate East. It bears the brand of London Transport, the similarly named predecessor of Transport for London who first introduced the roundel in 1933.
As part of the underground's 150th birthday celebrations in 2013, Transport for London installed these ye olde signs at Moorgate. The diamond-shaped device was created by the Metropolitan Railway in 1914. The faux-vintage signage remains in place today.
The red disc roundel was first introduced in 1908, and you can still see one at Covent Garden. More vintage roundels can be found at various museums around town. A set of Tufnell Park ones is on display at London Transport Museum's Acton depot, alongside many other examples.
One of the more creative official uses of the roundel can be found at Bethnal Green tube station. Similar clocks are on show at Gants Hill and Redbridge stations.
And finally... London Transport Museum's lovely little cafe serves its cappuccinos with a twist. Each comes with a chocolate sprinkle in the shape of a roundel. If you have one with your lunch, remember to mind the bap.
This article has covered official uses of the roundel, but many examples of unofficial use can be found. This Flickr group records imposter roundels from around the world, as did Annie Mole's now sadly defunct Going Underground blog.