Futuristic Superhighway: Well, now. They have lots of those. Apart from a few changes in materials, most of them look much like roads everywhere; the differences come in the technology buried in the road, such as the built-in power grid that lets vehicles recharge as they drive, and warms the road in winter to melt snow and ice, the road-grid that provides automated traffic management and routing (in cities and on the main routes, no-one drives on manual), the data connectivity, and the accompanying smart-road nodes that let the road itself provide you with local information and geosocial data.
While cargo delivery is mostly done at or below ground level (by wheeled – well, sphered, for ease of maneuvering in urban spaces – vehicles, even), the most common personal vehicle is the four-to-six-person vector-control flitter, a “flying car”; and while a fair few of them mingle with the freight traffic at ground level, even more are herded into the flyways at various heights above the highways to take them wherever they wish to go, all delineated by augmented-reality signs and guides (and, in urban areas, by actual building spars holding support hardware.
Oddly enough, while there is a lot more traffic than there used to be, the roads really aren’t that much wider, which is a combination of so much traffic being shunted into flyways above the highways, and of the road-grid automation letting cars pack much more closely together, when needed, than merely biological reflexes would support with the same safety margins.
And, of course, some changes in road features; the embarkation loops and bays where vehicles can stop to deposit or pick up their drivers before heading off to park themselves (and, obviously, no vehicles parked by the side of the road when the automation can let them drive themselves off and stow themselves in a buried parking hive until called for); the skymerge lanes in the middle of the highways where flitters transition between highway and flyway; and in general, a distinct lack of road markings and traffic signals which are all handled by AR systems – or at the very least, the vehicle HUDs – or automation in lieu of messy street furniture.
(And sometimes, they do have highway tunnel systems, extraordinarily long bridges – of multiple, even many miles – air-conditioned or environmentally supported highways on hostile worlds or in hostile regions, or highway tubes that dive beneath the oceans.)