cycle sub by duncan ledingham from uk

The idea behind the Cycle Sub was to get people on their bikes, and be allowed to ride in a safe environment. Similar to underground tube systems, it would have main drop off points. Although it may not be as direct as cycling on a road, it
would be safer and more enjoyable due to less traffic and fumes. It would swoop above and below the city streets with a back draft used to aid cyclists up small hills. The design is mainly directed at commuters cycling through rush hour periods. The idea spurred from cycling on busy urban streets with the backdraft concept coming from the chimney effect of a building.