Replace Tube trains with travelators, say architects
Conceptual plan turns Circle Line into a 17-mile-long moving walkway, offering three different speeds
An architecture firm has unveiled a conceptual plan to turn London Underground's much-maligned Circle Line into a 17-mile-long moving walkway.
The idea, from architects NBBJ, consists of replacing all of the trains on the route with a set of three travelators. Each walkway would move at a different speed, ranging from 3mph to 15mph.
"The result would be considerably quicker, more enjoyable and healthier journeys," NBBJ said in a statement. It added that the Circle Line travelator would "likely become one of London's most efficient and unusual modes of transport".
The architecture firm has so far only released a series of images depicting the concept. However, critics have already suggested that there may be some underlying issues.

Gizmag highlights one such issue, explaining: "While moving walkways are used by a large number of travellers in airports worldwide, being required to navigate such a system would no doubt prove tricky for the elderly and some disabled people."
According to The Independent, the NBBJ project is more like the "trottoir roulant rapide" that opened at Montparnasse station in Paris in 2002. Although it was initially a success, it had to be slowed down from 6mph to 3mph after passengers were repeatedly injured trying to get off the faster part of the walkway.[[{"type":"media","view_mode":"content_original","fid":"84344","attributes":{"class":"media-image"}}]]
Commentators have pointed out the similarities between NBBJ's idea and Caves of Steel, a novel by famous science-fiction writer Isaac Asimov.
In Asimov's work, "caves of steel" – vast city complexes covered by huge metal domes, where commuters transit on moving travelators between malls and their homes – are constructed to counter over-population.
Daily Mail notes that in the book no one ever leaves the domes, and most of the population suffers from extreme agoraphobia.
This is not the first ground-breaking idea for London that the architecture firm has produced. In March, NBBJ developed proposals for two twisting towers in North Greenwich, London, that would bounce light between them down to a public space that would otherwise be in their shadow.
"We like to push the boundaries of what is achievable with design computation by developing new applications like the No Shadow Tower," the firm said.