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Today, asphalt roads are a luxury many people take for granted. They are the lifeline of our country, leading us wherever we need to go. But how did we get here, and where did the idea for asphalt pavement originate?
For history buffs, the name John McAdam is a familiar one. In 1816, McAdam introduced The Present System of Road Making, revolutionizing road construction with a new method: compacting crushed stones into a cohesive surface. His core principle—using the right materials in the right way—helped bring road building out of antiquity.
McAdam also advocated for government involvement in road construction, much like the Romans had centuries ago. His method, known as “macadamizing,” was a breakthrough, but it had one flaw: durability. Something was missing—something that would make roads last longer. That missing piece was asphalt.
An illustration of the first macadamized road in the U.S. 1823, By Carl Rakeman – US DOT
Interestingly, asphalt’s introduction to road construction happened by accident. In Europe, naturally occurring rock asphalt had been used for sidewalks and bridge decks as early as 1802. However, its application was time-consuming and inefficient.
Then, fate intervened. A pile of rock asphalt chunks fell from an overloaded cart onto a macadam road. As wagon wheels crushed and compacted the material under the summer heat, the first asphalted macadam pavement was unintentionally created.
Seeing the potential, European engineers began intentionally combining crushed asphalt rock with McAdam’s road-building principles. By the late 1800s, this method had gained popularity—Paris boasted 20 miles of asphalt roads, while London had 15.
But in the U.S., rock asphalt was far too expensive to import. The Americans needed their own solution. Enter Belgian-born chemist Edward J. de Smedt. After studying Europe’s success with rock asphalt, de Smedt moved to America and, in 1869, used natural asphalt from Trinidad to engineer the first hot-mix asphalt road surface in Newark, New Jersey.
Over in Washington, D.C., N.B. Abbott built on these developments, earning the first U.S. patent for bituminous hot mix pavement in 1871. Over the next 50 years, innovation continued. The first asphalt plants, steam rollers, portable pug mills and screeds were introduced, pushing the industry forward.
By the 1920s, hot mix asphalt was being produced faster than it could be laid. But new trucks and mechanized equipment in the late 1920s and 1930s changed that, allowing for more efficient road construction.
In the 1950s, President Eisenhower prioritized the creation of a robust highway system. His “Grand Plan” called for a nationwide upgrade of roads over a 10-year period. At the 1954 Governors’ Conference, the stakes were laid out:
A modern interstate highway system, he argued, would unite the country socially, economically and militarily.
This led to The Interstate Decade (1956-1966), during which over 23,000 miles of interstate highways were built. But as road networks expanded, the need for maintenance became more evident.
Click here for Part 2: The Evolution of Pavement Preservation in the Asphalt Industry – Learn how pavement maintenance has developed!
In the 21st century, America contains over 4 million miles of public roads. Maintaining these vital pathways is more important than ever. Check out the “Report Card” for how the United States’ road infrastructure is doing today.
Editor’s Note:
For further reading, check out the book “Paving the Way: Asphalt in America” by Dan McNichol, where information for this article was sourced.
