London Underground’s Circle Line could be remade into a 17-mile-long moving sidewalk.
Dezeen reports that architecture firm NBBJ pitched a concept where the train service would be removed and three sets of "travelators," as they are called, would be installed. The walkways would run next to each other and operate at three speeds, from the low speed of 3 to 9 mph to the maximum speed of 15 mph.
NBBJ said that the plan would make transportation faster by eliminating the need to stop at stations.
The 36-station Circle carries 114 million passengers annually and has been in operation since 1863. The line runs in both directions around a loop around central London, with an extension that juts off the circuit.
The Daily Mail writes that the Circle Line has some issues. It can only hold up to eight trains at a time, and trains can only reach a top speed of 20 mph. In ideal conditions, trains complete the loop in an hour, but because of the system’s age and the amount of rider congestion, delays are frequent.
With the travelator, walking at a 3 mph clip at the 15 mph top speed will get a commuter around the loop in just 56 minutes. The walkways could hold up to 55,000 people at once.
Wired reports that all practical considerations, like price, construction, and energy usage, have yet to be determined.