History and Engineering of Global Road Networks

Vocabulary and key facts regarding the history, engineering, and cultural significance of international road networks from ancient times to the modern era.

Roman Empire Population

Estimated at more than $55$ million people at its height during the second century $A.D.$

Emperor Trajan

The ruler under whom the Roman Empire reached its greatest extent of nearly $2$ million square miles in $A.D.\,117$.

Via Augusta

A paved highway constructed by Octavian between $8$ and $2\,B.C.$ that ran over $900$ miles through ancient Hispania.

Dioptra and Groma

Surveying tools used by Roman engineers to lay out orderly city grids and construct long, straight roads.

Roman Milestones

Markers installed along roads where more than $8,000$ have been found with Latin inscriptions showing distances to the nearest city or way station.

Brughmans' Road Research

A $2025$ study identifying that the Roman road network extended to $185,896$ miles across almost $1,544,409$ square miles.

Lombard Street

A San Francisco road famous for its $8$ hairpin twists that descend down the hills.

Abbey Road Studios

The London recording facility located on Abbey Road where the Beatles recorded all of their albums.

Broadway Theatre District

The ten or so blocks located between $42^{nd}$ and $53^{rd}$ streets on New York's most famous road.

Hollywood Boulevard

A Los Angeles road embedded with over $2,500$ stars, including the first permanent star created for Stanley Kramer on $March\,28,\,1960$.

Lan Kwai Fong

A Hong Kong street famous for its nightlife and more than $80$ restaurants and bars.

White Rim Road

A $100$-mile road in Canyonlands National Park that loops below the Island mesa top.

Tianmen Mountain Road

An $11\,km$ road in China with $99$ bends that reaches a natural mountain hole located $131.5\,metres$ up.

Guoliang Tunnel Road

A $1.2\,kilometre$ path built by $13$ villagers over $5$ years to connect their village to the rest of the world.

Route 66

Known as the 'Main Street of America,' this $2,400$-mile stretch of road passes through $8$ states from Chicago to Santa Monica.

Silk Road

A network of trade routes starting around $130\,BCE$ during the Han Dynasty that remained active for over $1,500$ years.

Royal Road of Persia

A $2,700\,kilometre$ road built by Darius the Great in the $5^{th}$ century $BCE$ that couriers could cover in just $9$ days.

Inca Road System

A network of more than $40,000\,kilometres$ that used hanging rope bridges and cliff-carved paths to connect Cusco to distant regions.

Inca Trail

The most famous road of the Inca system that leads to the site of Machu Picchu.

Amber Road

A northern trade network that carried fossilized tree resin from the Baltic Sea to the Mediterranean.

King’s Highway

One of the oldest continuously used routes in the world, running from Egypt, across the Sinai Peninsula, and through Jordan into Syria.

Grand Trunk Road

A $2,500\,kilometre$ highway from Bangladesh to Afghanistan developed in the $3^{rd}$ century $BCE$ and later improved by Sher Shah Suri.

Macadam

A road construction method from c. $1820$ using crushed stone in shallow, convex layers and a raised roadbed for drainage.

Tarmacadam

A road surface method patented by Edgar Purnell Hooley around $1900$ that involves spraying hot tar or bitumen over stones.

Pavement

The general term for any durable surface laid over ground intended to support traffic.