Re: Transportation in ultra-dense urban areas.
- That would be very interesting, and probably make traffic a little
less intense. However, in cities that have a sidewalk level and a
second-story sidewalk level (typically indoors) among buildings,
critics have found that the upper-class people typically get to use
the second-storey walk and the poorer people are left at street level.
Your proposal for outdoor roads and sidewalks might prevent this though.