On the Road Again

As summer approaches at an alarmingly fast rate, we might find ourselves flocking more towards planes, trains, and automobiles… and bicycles… to travel around and get out of the house. Transportation infrastructure as a whole can bring about some great memories, such as road tripping or soaring past the landscape in a train. It can also bring some horrible ones, such as getting stuck in traffic or dealing with a public transportation delay. All in all, this infrastructure is usually able to get us where we want to go, even if it takes longer than we expected. This week is in honor of the roads that pave the way to our destination. We’ll take a brief look at the history of roads as well as current trends in road infrastructure around the world. So put the car in Drive and let’s get to it. Just kidding; driving while reading Grow Weekly at the same time sounds extremely dangerous.

A Brief History of Roads

Some of the earliest constructed roads that we have evidence of date back to around 4000 BC in the area of Mesopotamia, or near present-day Iraq. These roads were paved with stones and located near the ancient cities of Ur and Babylon. There’s also evidence of timber “trackways” in swamps in the area of Glastonbury, England around this time (closer to 3800 BC). Interestingly enough, this was slightly before the wheel was even invented, with evidence showing that the wheel came about closer to 3500 BC. The Ancient Egyptians also showed some evidence of roads back around 2500 BC, with the Pharaoh Cheops having a road built to lead to the Great Pyramid, though this road was not used for transportation. The Silk Road may also come to mind when thinking about very old roads, but this was more of a “trade route” as opposed to an actual paved road.

A very old wheel… or just a block of cement?

A very old wheel… or just a block of cement?

Fast forward some time, and you had other civilizations like the Carthaginians around 800 BC building stone-paved roads and the Persian empire around 500 BC building a road that covered close to 1,800 miles! Through this history of roads, the Roman Empire seems to have taken the cake for building some of the most extensive, well-engineered roads. At the height of the Roman Empire, almost 53,000 miles of road were maintained throughout England, Western Europe, and the Iberian Peninsula. Roman roads used a graded soil foundation along with several layers of various stones and sand or mortar to provide a well-draining, stable surface. Roman roads were also for public use.

Some Roman roads have been resurfaced a number of times and are still used today.

Some Roman roads have been resurfaced a number of times and are still used today.

In the Americas, the Inca Empire established a network of 24,000 miles of road around 1500 AD. The incredible thing about this? It was all done by hand - without wheels or iron - and many of the roads still exist today, though they’re only traversable on foot. They are incredibly resilient roadways, and the Inca Road was designated as a UNESCO World Heritage site in 2014. Unfortunately, the road was so effective that it enabled the Spanish conquistadors to travel more quickly throughout the Inca Empire and conquer it. 

Jumping back to Europe in the early 1800s, the first “modern” roads were being built with credit given to two Scottish engineers, Thomas Telford and John Loudon McAdam. Telford had made the contribution of installing a heavy rock foundation  for support and raising the center of the road to aid in water runoff. McAdams contributed to road-building through his use of soil and crushed stone aggregate which were then packed down to create a hard, flat surface to travel on. Later in the 1800s, the integration of tar-like asphalt for these types of roads began in greater number. The Champs-Elyees in Paris, France was the first road to be paved with asphalt back in 1824. 

Roads became much more like “modern” roads during the 1800s.

Roads became much more like “modern” roads during the 1800s.

Roads continued to be constructed in this way. A surge of bicycle use in the United States in the late 1800s actually resulted in the “Good Roads Movement”, which laid the foundation for road infrastructure for automobiles that were still in their infancy at the time. 

States took the initiative, and by 1917, each state had some form of a highway department. During the 1910s, the Lincoln Highway was formally dedicated as one of the first Coast-to-coast highways for automobiles running from Times Square in New York City to Lincoln Park in San Francisco. Much of this Lincoln Highway became part of current-day Route 30. Road infrastructure continued in the early 1900s, along with efforts to extend roads into rural areas to improve farmers’ access to markets. Throughout much of these past 100 years, not much has changed in terms of road-building techniques, although road networks have continued to expand with fascinating feats of engineering, such as the Eisenhower Memorial Tunnel built in 1973 in Colorado. Safety has also continued to improve, such as with traffic lights in the early 1900s or the first automatic “Don’t Walk” sign for pedestrians installed in New York City in 1952.


Side note:

The first parking meter in the United States was installed in 1935 in Oklahoma City. The company that patented it was the Park-o-Meter company, which is also credited with patenting and selling the first fully electronic parking meter in 1992.

Where does this Road Go?

Soooooo where are we headed? Well, some interesting insight is provided from a few different sources as to trends in road infrastructure. 

Price is always an important factor when it comes to.... well, anything really. It seems that the cost of road construction in particular integrates a few interesting variables. For one, the cost of road construction seems to have increased over time at least in the United States, even accounting for inflation. For example, the cost of building one mile of interstate in the 1980s was 3 TIMES higher than what it cost in the 1960s after being adjusted for inflation. 

Some postulate that this increase in cost is caused by a parallel increase in home prices, incomes, and “citizen voice”. An aspect of this increase in “citizen voice” is the increased emphasis on environmental reviews and regulations which in turn increase the “wiggliness” of roads. Yes, I did mean to use the term wiggliness. With greater concern for the environment, roads have to meander around and adjust to changing directions in order to avoid potentially fragile ecosystems (as well as expensive neighborhoods). Another factor that may be responsible for the increase in cost per mile of road is the increase in the quantity of labor used to build roads (not the cost of labor). Despite these increases in road costs per mile, state and local spending on roads (which account for a greater share than federal spending on roads) have remained relatively constant over time.

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It’s also interesting to note that the cost per mile of road maintained is drastically different in each state. New Jersey has substantially higher costs for their transportation department per mile of road compared to every other state.

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The reason for this discrepancy among states is actually not well-understood. 

Spending on road infrastructure on a global scale has a few other factors at play, with one being the level of corruption or conflict in a country. Countries that have higher levels of violent conflict or corruption result in reliable increases in the cost of roads on a per-mile basis. This is especially important for countries with smaller or developing economies that would benefit from greater road connectivity. In most cases, roads are publicly funded by the government as opposed to other industries such as railway or electricity which are frequently privately funded. So it almost creates a vicious cycle: higher road costs due to conflict and corruption →  inability to fund expensive roads → economic development hindered by lack of national road infrastructure. 

One other facet of roadway financing in countries with small or developing economies is that wealthy donors or philanthropists have shifted support in recent decades from support for infrastructure (such as roads) to support for social priorities (such as healthcare). 

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On the global stage, the total length of roads developed is increasing over time (which is somewhat understandable). Various models come up with different projections, with one estimating that an additional 3.0 to 4.7 million kilometers of road will be added by 2050, which is an increase of 14-23% compared to present-day. Another estimate puts it at an additional 14.8 to 25.3 million kilometers of road by 2050, which would be closer to an increase of 35-60% compared to 2010. One aspect to consider is the definition of “road” and whether that includes paving, but in general, that’s a fairly significant increase. The 2018 article published in Environmental Research Letters also states that these increases in road length are projected to occur predominantly in developing nations in some of the last remaining “wilderness” areas on Earth, such as the Amazon Rainforest and the Congo basin. 

Roads certainly aren’t the only way to get from here to there, but they remain closely tied to our past - and likely our future as well - as a human species. Roads can both connect cities and divide neighborhoods, save lives by shortening response times as well as take lives due to accidents. They can also just be slabs of rock and tar. Either way, next time you find yourself coasting down the highway or riding a city bus or even stuck in traffic with a full bladder... just take a moment to appreciate the road that made your travel possible.

To Think About…

  1. Do you think road-building methods or road designs will change in the near future (e.g., will we still use asphalt, traffic lights, crosswalks, exit ramps, etc.)

  2. Do you think your local, state, and/or federal government should increase spending on road infrastructure? Do you think maintenance of existing roads or development of new/expanded roads should be prioritized?