Take a metro area. You have a freeway or hiway going across. Connecting different areas of the city.
The idea is to build raised bike ways atop. Such that these bike ways are 2 stories up or more. They'd be 10 feet wide and there will be one on each side of the freeway, for different bike travel directions. One would have to ride up hill or carry their bike or elevator to get on one of these. The bike way would be fully cages with chicken wire net for protection. It will alow have a grade, 2 to 5 degrees, allowing bikes to accelerate to 20, 30, or even faster mph while the ride don't even have to pedal.
To get to these bike ways there will be many bike lanes along major routes to the highway.
Thus you have it, an efficient way for people to travel around large metro areas on a bike. Using gravity to move a biker from point A to point B.
What are your thoughts?