A highway is a mono-functional road, designed to carry cars from one place to another at a maximum speed. But, sometimes highways don’t carry so many cars as expected,  and other uses start to appear.

An example of the re-use of highways was the Antonio Segni Bridge in Northern Rome, the east-west road in the photo here below.

Planned as a part of the Milan-Naples highway, Bridge Antonio Segni has been cut from the rest of the network when the motorway was re-routed on a more external route. Closed to traffic for almost ten years, it has become the favorite place for pedestrians and cyclists’ sunday strolls. When it was opened to motorized traffic, few cars passed on the Bridge, and pedestrian and cyclists still continued to use its sidewalks as a shortcut to reach otherwise far neighborhoods.

Some improvement could be made in order to make this bridge a more interesting place:

• wider sidewalks and zebra crossings.
• smaller roadway and lower speed limits
• more pedestrian connections to nearby neighborhood.
• a landscaped median.

2016 edit: several projects have been proposed for this bridge (see here, here and here) but no real intervention has been made. Apparently, nobody cares of this bridge anymore, and it’s simply left to decay.