What is the best material to make a road out of?

Solar panel tiles.

Rocks and gravel.

And it doesn’t get more gravelly than Dave Van Ronk.

No no roads!!! Zip lines everywhere!
No emissions, no fossil fuels, cheap to make and repair. We could climb a few times to the towers, continue zipping, so it’s exercise, too.
Then for the disabled, we could use the old ‘streets’ as conveyor belts, like in the Bee movie.

A mixture of about 50/50 asphalt (like normal roads are made of) and ground up tires.

Magnets, so the vehicles don’t even touch the surface but float frictionless down the track

Double the depth of the roadbed, they made roads for the Autobahn 80 years ago that are still drive-able! From the the link, “But some of the most important differences between American and European expressways lie well beneath the surface. All highways are built by bulldozing softer subsoils and either tamping them or replacing them with more durable dirt or gravel. But in Germany the roadbeds tend to be 1.5 m or 1.8 m (5 ft. or 6 ft.) deep, twice the U.S. average. European engineers also devote more time and money to designing roadbeds that resist frost and have excellent drainage, addressing two problems that play havoc with U.S. thoroughfares. Each step, from laying the subsequent gravel or concrete layer to applying the asphalt surface, is taken with long-term durability in mind.”

@flutherother Some friction is good. Like when you want to turn a corner…

Concrete is the best base. It gets topped with asphalt, because weather has effects on whatever we use, and asphalt is easily replaceable. Concrete is harder on tires than asphalt too.
There may be substances more durable to use for topping the concrete, but do they wear tires quickly? Are they cost effective?
I worked for the DOT for a while, and there are a lot of things which affect the decision about what to use for roads.
US roads were concrete long ago, but it played hell with tires.
Different regions have different formulas to fit their particular environment.
Often, when you see a sign prohibiting trucks it is because that particular road was not made to take the weight.
Weather, quakes, traffic weight, safety, and other factors come into deciding what formula to use for roads.
Even the degree of a curve makes a difference in depth.

@kritiper Why make roads with corners? It’s far more efficient to travel in a straight line from A to B.

@flutherother Maybe we don’t need roads in the future? Flying cars will be the future.

Better to have underground tunnels to reduce wind resistance.

@flutherother Ohh TMNT, Teenage Mutant ninja Turtles – sub-terrarium vehicles?

Only faster!

@flutherother You come out west to the Rocky Mountains and I’ll show you!

As @Patty_Melt writes, concrete is the best option today.

Bricks are more durable. But the installation cost is high (you can’t pour bricks), so they went out of favor 100 years ago.

In lots of old side streets here in Chicago, you’ll find brick paving. In major road projects you can see brick layers intact under subsequent asphalt pourings.

The most interesting is under viaducts, where railroads cross major streets.

They never pour over the old bricks under the bridges, because it would shrink the distance between the road and the bridge beams overhead. They leave the bricks to maintain the headroom.

So where we have miles and miles of new roads, the brick surfaces are still there when you drive under a railroad bridge.

RDG, I’m going to address your thoughts on graphene here, because hijack just takes so long to load.
There is no way.
The expense would be beyond astronomical.
It is highly conductive, so it would be lethal with downed lines.
I haven’t seen any, but I am guessing it is also too smooth for any good traction, but that is just a guess.
It would actually be cheaper and safer to use six inch thick layers of saran wrap.

And no, that wouldn’t work well either.