THE PAST

a history of hitting the

ROAD

Humans have been clearing trees

and burning brush to transport food

and attack our enemies for more than

10,000 years, but Mesopotamians

invented some of the first paved

roads to make more transit-friendly

cities around 3000 B.C. Workers

molded thousands of identical clay

bricks, dried them, then arranged

them like tiles. To keep paths from

crumbling every time a cow kicked,

they glued the blocks together with

bitumen, a naturally occurring semi-

sticky petroleum that we still use as

a binder in asphalt today. But this

ancient population bothered with

the labor-intensive method only on

streets with religious significance or

high military value.

While all road technology might

not lead back to Rome, the Roman

rocks

and

bricks

Empire did build some of the longest

and most durable pathways in the

ancient world. Builders recessed rock

and gravel layers into the ground for

stability. Closer to cities and in other

prominent areas, pavers topped these

layers with hard stones to create a

more polished look.

At its height, around A.D. 100, the

Empire presided over a combined

50,000 miles of highways, which

allowed soldiers and merchants to

move swiftly throughout Europe and

Asia Minor. Some of these timeworn

passages are still functional today.

The Via Appia, which runs from

Rome 350 miles southeast to the east

coast of Italy, supports automobile

traffic on select stretches— though

it has required quite a few overhauls

over the past two millennia.

by Jake Bittle icons by Hubert Tereszkiewicz

Today’s streets have it harder than their ancestors did. Instead of

feet, hooves, and wooden wheels, they shoulder semis and SUVs.

As we’ve developed new ways to zip around, we’ve also changed

the makeup of the routes on which we travel, transforming gravel

paths into asphalt superhighways. Challenges such as extreme weather and

carbon emissions mean our expressways must evolve even further, so engineers

are turning to futuristic fixes to keep traffic flowing. Here’s the story behind

that long and winding journey—and where it’s going next.

PAS T

in the

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