If you have even the least bit trouble walking, city subway systems are bad news. Getting to the station is trouble enough. Then there’s the descent. The deepest station on the London Underground is nearly 200 feet below the surface; in New York, it’s 180. Riders headed for the trundling abyss face a maze of stairs, escalators, and elevators that are all too often out of service. Just a quarter of London's Tube stations have “step-free access." You're better off taking the bus.

Until now—or at least, the near future. Maybe. The architecture firm Weston Williamson, which has worked on a number of major London Underground projects, is hoping to install a radical elevator design in Tube stations. The Multi, from German engineering outfit Thyssenkrupp, is a mag-lev elevator system that doesn't just go up and down—it goes sideways. It's rather like Willy Wonka's great glass elevator, minus the bit about flying into space.

Weston Williamson director Chris Williamson admits he was skeptical when he heard of the idea. But now that Thyssenkrupp is actually building one of these crazy things, in an 800-foot test tower in Germany, he wants one in the Tube. The Multi is “a fantastic, game-changing revolution,” he says. It can help increasingly overcrowded public transit systems move people—and not just those with disabilities—into, around, and out of stations.

How It Works

First introduced as a concept in 2014, Multi uses magnetic levitation to propel multiple cabins through one loop-de-loop shaft at the same time. It’s the same tech used in a few (non-American) rail systems: Magnetic coils on an elevator shaft track repel magnets on elevator cabins, floating rider-filled boxes to their destinations. Making it move sideways is just a matter of building a horizontal shaft.

To get folks into a subway station, the Multi could start its journey in skyscrapers themselves. Riders could call a cabin right to their office floor, and the system would organize riders making trips to the same subway platform together. No walking to the Tube station: The Multi would deliver them straight to the train. It’s ideal for subway systems that organize different lines on top of each other—no more getting off an escalator halfway for another escalator. In ThyssenKrupp's vision, Multi’s cabins fit just six to ten people, but would arrive every 15 to 30 seconds. And if traffic doesn’t demand all the elevators at once, a few can temporarily retire, saving energy.

Can It Work?

The setup also saves space. Established subway systems, already built around foundations, water pipes, telecom equipment, and the occasional rat king, don't have room to spare for new transit options. But Multi needs only one shaft.

London's not the only city that could benefit from this sort of accessibility. In New York, for example, just 20 percent of subway stations are wheelchair-friendly. Elevators and escalators are also enormously helpful to “the elderly, young children, and people who have baggage,” says Adam Forman, a senior researcher with the policy think tank Center for an Urban Future. For those who have trouble getting around, elevators that take them exactly where they're going can't come soon enough.

Sure, a Great Glass Elevator brings up the the standard government problems: procurement, construction, maintenance, cost. ThyssenKrupp won't say how much a Multi system would cost, but argues increasing capacity without making stations any larger “is gold dust for metro station developers."

First, though, the company must prove the concept in its test tower, and London for Transport would need to approve its construction. The agency would be taking a risk: Just look at New York, which had no end of trouble with the fancy-ish elevator in the extension of its 7 subway line.

Still, you can't argue with increased efficiency, or accessibility. Or pure laziness.