Historic Route 66 will always be the "Mother Road," an endearing snapshot of America's past, a cultural landmark and the ultimate road trip destination. However, Route 66 is no longer used the way it once was. In fact, the last piece of Route 66 was officially decommissioned in 1985, following the construction of Interstate 40 in Arizona. But what exactly is an interstate, and how does it differ from a (former) U.S. federal highway, like Route 66? The answer illustrates the way America expanded after the second World War, and how the Mother Road went from being one of the main transportation routes of the West to a peek into a different time.
A New Kind of Road
The origins of the U.S. Numbered Highway System, as embodied by roads like Route 66, go back several decades further than the Interstate System — not too long after cars became an important part of life for many Americans, in fact. In the 1910's and 1920's a series of "auto trails" were built across the country by several local booster organisations. While they represented a step forward for the growing number of automobile drivers in the country, these routes varied wildly in quality. Many boosters built roads in ways that would allow them to collect dues from as many businesses as possible, rather than the most direct routes.
By 1925, the auto trail system was beginning to become unsustainable, as those booster organisations stopped performing road maintenance, and the federal government stepped in. That year, the U.S. Secretary of Agriculture began working with state governments to create a nationalised system from coast to coast. Route 66 was born out of this initial road-building push. Unlike many of the routes on previously existing auto trails, Route 66 was explicitly designed to run through several smaller towns, giving farmers access to a major road to move crops on. Today, this lends Route 66 a part of its rural, off-the-beaten-path charm.
The Post-War Expansion
Major changes came to the U.S. road system in the years following World War II. Car ownership skyrocketed, and many of the routes created in the 1920s and 1930s were insufficient to handle growing traffic. In addition, new anxieties created by the new reality of nuclear weapons and growing American hostilities with the Soviet Union meant that some in the military wanted a system for evacuating major cities quickly, in the event of an attack. In 1956, President Dwight D. Eisenhower signed the Federal-Aid Highway Act, establishing the construction of a new, larger system of roads, called the National System of Interstate and Defence Highways.
In the years following 1956, interstate highways which typically had more lanes, fewer stopping points and higher speed limits than routes, grew in popularity and continued to be expanded upon. Today, the U.S. Interstate System stretches for 46,876 miles.
Over time, a series of new interstates began to cover the area of the American West that had once depended on Route 66 as its primary transportation route. Interstate 40 stretched from Oklahoma City to southern California, providing a speedy option for parts of Texas, Arizona and New Mexico. Two interstate highways built shortly after, I-55 and I-44, soon covered much of the rest of the region. In 1979, the American Association of State Highways and Transportation Officials made the decision to remove the Route 66 designation. While the road was no longer an official part of the U.S. Numbered Highway System, many municipalities decided to erect signage signifying that they were along "Old" Route 66. Whether paved over by an Interstate or maintained as state or local roads, the majority of the Mother Road remains, ready for you to explore.
Identifying a Route Vs. an Interstate
One of the key differences between a state or federal route and federal interstate are the number of access and exit points. While many U.S. highways go directly through towns and have many roads that drivers can turn on, Interstates tend to only have a select number of exits, utilising on and off ramps rather than directly intersecting with other roads. Interstates also tend to have higher speed limits and more lanes, allowing for more traffic flow. Routes, meanwhile, take a bit more of a "scenic" approach.
One of the clear ways that you can identify if you are on a U.S. highway or an interstate is through signage. U.S. highways typically appear in a white shield on a black sign, although the exact specifics and shape of the shield may vary. Interstate signs, meanwhile, are more visually consistent. They are typically demarcated with a blue shield with a red top. The interstate number can be found in the centre of the shield with the world "Interstate" above it, in the red section. The state and local roads you'll encounter driving along old Route 66 also come with their own unique iconography, often incorporating either the shape of the state or a symbol that is unique to them. New Mexico, for example, utilises the sun symbol of the indigenous Zia tribe, which also appears on the state flag.
For the road trip of a lifetime, you simply cannot top a drive down Historic Route 66. We can't wait to take you back out on The Mother Road once it is safe to do so. Our next planned tour is scheduled for July 2021. You can look forward to an incredible 20 nights travelling from Chicago to Las Vegas, exploring the best antique cars, roadside attractions and natural features that America has to offer. All of our tours are guided a team of Australian professionals who know all of the best sites. While you wait, you can stay connected and check out more views of the adventure ahead at www.route66tours.com.au.