US Highways



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History of the US Highway System [Old Style Mississippi US 51 Shield ]

From Dirt Paths to Superhighways

Before the Interstate Highway system brought fast, limited access highways to the United States, there was, and still remains, another nationwide system of highways that enabled travelers to follow standardized routes to any part of the nation. This system, known as the United States Highway System or simply as "US" highways, was the first time in history that a national standard was set for roads and highways. This system of highways existed

This system was created by the Federal Aid Highway Act of 1925 as a response to the confusion created by the 250 or so named many named highways, such as the Lincoln Highway or the National Old Trails Highway. Instead of using names and colored bands on telephone poles, this new system would use uniform numbers for inter-state highways and a standardized shield that would be universally recognizable. The most important change was that this new system would be administered by the states, not by for-profit private road clubs. Even then, people decried the idea of giving roads numbers since they felt numbers would make highways cold and impersonal.

The Automobile

At the beginning of the twentieth century, automobiles were a novelty that only could be enjoyed by the very rich. Most Americans contented themselves with either using the horse and buggy or taking the railroads when they needed to go on long trips. Getting around in large cities was fairly easy due to comprehensive networks of streetcars and subways. Even though it is hard to believe today, especially in California, it was generally thought that autos would never catch on. In short, in the early part of this century, there was simply no need for a good system of roads.

Henry Ford changed the status quo with his revolutionary production line techniques. He took the idea of standardization and applied it to creating standard parts for automobile manufacturing. Cars could be produced cheaply, although a few sacrifices had to be made. Ford once said that "you can get the Model T in any color you like as long as it's black." For the first time in history, workers in a factory could afford the products they manufactured. The Model "T" soon became a common sight throughout the United States. A testament to their popularity is that over 16.5 million were sold, a record which was not broken until 1972 when the Volkswagen Beetle surpassed that mark. Needless to say, this created a huge demand for good roads.

The Rise of Named Highways

Lincoln Highway Marker

Colored bands on telephone poles used to mark the named trails.

At the beginning of the century, the supply of good roads was nowhere near the growing demand. Most roads at the time were little more than improved wagon trails. In fact, many of the major "highways" were actually vestiges of old trails, such as the Oregon Trail or Santa Fe Trail. There were paved highways, but most were cobblestone and almost all were in major cities. Good road organizations appeared to remedy this situation. The American Automobile Association and the Automobile Club of Southern California (they were separate organizations originally) were formed in California to promote better roads. Additionally, many trail associations were created to address the need of having marked interstate highways; this was the birth of the named highways. The Lincoln Highway, from New York to San Francisco was the first and by the early 1920s many highway organizations were formed which placed and promoted their own routes. By 1925 there were over 250 named highways, each with their own colored signs often placed haphazardly, a fact which created great confusion.

Several problems arose with the named highways. The lack of a central organization to dictate the placement of interstate highways left the door open for self-serving organizations to "relocate" the famous named roads so they would pass through their cities.  More frequently, though, the lack of coordination between states through which the transcontinental routes ran caused confusion since the route was often not even straight. The need for a system of standardized interstate highways had evolved.

The Federal Government Becomes Involved

By 1924 it became clear that a single, unified system of highways was necessary. In that year, the American Association of State Highway Officials (AASHO, today's AASHTO) passed a resolution requesting the Secretary of Agriculture (the Bureau of Public Roads was in this department at the time) to investigate the possibility of creating a system of standardized highways.

Giving highways throughout the United States a standard numerical designation was a radical idea but at the same time fit in with other innovations at the time.

For example, by the 1920s road building was also becoming a standardized process. Road building technology advanced in a logarithmic manner, allowing good roads to be built just about anywhere. Of course, by today's standards these roads are inadequate in all aspects, including width, sight distance, grade, etc. At the time, having a paved road going through places such as the Cajon Pass and over the Ridge Route was an incredible boon.

The Beginning of the End

The passage of the Interstate Highway Act in 1956 spelled the end of the California US highways as the leading. The proposed system would supplant many of the US routes with divided Interstate highways, a fact that obviated the need for them. California, since the late 1930s had been pushing for creating divided highways and a comprehensive freeway and expressway system and by the late 1950s, many of the US routes had already been converted to freeways and expressways or were slated to do so. It appears the original plan was for the Interstate Highways to be co-signed and routed with their corresponding US highway and from about 1960 to 1964 this is exactly what the Division of Highways did.

Despite this effort, it was clear that there was no purpose in maintaining many of the old US highways. Legislation was enacted that would change the face of California's highway system. One thing that was changed was that all highways would have the same sign and legislative number. For example, US 99 was Legislative Routes 3 and 4 but was Sign Route US 99. This legislation also eliminated over half of the existing US highways and renumbered and adjusted many state highways. Portions of US 99 became Legislative Route 5 and were signed as Interstate 5, while about half of its length became Sign Route CA 99 and was Legislative Route 99 in the books.

Almost half of the US highways in California were taken off the map. The list below shows their dispostion.

  • US 6: Shortened to Bishop and replaced by SR-1, SR-11, I-5, SR-14.
  • US 40: Eliminated and replaced by I-80.
  • US 66: Shortened to Pasadena and replaced by SR-2, SR-11.
  • US 66 Alternate: Eliminated (no state routes replaced it)
  • US 70: Eliminated and replaced by I-10.
  • US 91: Eliminated and replaced by SR-1, SR-91, I-15.
  • US 99: Initially shortened to Los Angeles and replaced by SR-111, SR-86, I-10.
  • US 101: Shortened to Los Angeles and replaced by I-5.
  • US 101 Alternate: Eliminated and replaced by SR-1.
  • US 101 Bypass: Eliminated and replaced by rerouted US 101.
  • US 299: Eliminated and replaced by SR-299
  • US 399: Eliminated and replaced by SR-33, SR-119, SR-99.
  • US 466: Eliminated and replaced by SR-46, SR-99, SR-58, I-15.

More US highways were to be decommissioned or shortened, although most of them remained signed until their corresponding Interstate highway was completed. I've added the end date for each in parentheses.

  • US 50: Shortened to Sacramento and replaced by I-580, I-205, I-5, SR-99. (1972)
  • US 66: Eliminated and replaced by SR-66, I-15, I-40. (1972)
  • US 60: Eliminated and replaced by SR-60, I-10. (1972)
  • US 80: Eliminated and replaced by I-8. (1972 - San Diego Co.; 1974 Imperial Co.)
  • US 99: Eliminated and replaced by I-5, SR-99. (1967)

Another major route renumbering occurred in 1972 that set in stone what the remaining US highways in California were to remain. The most significant item, to the US highway buff, is the elimination of US 395 south of Adelanto, which was replaced in whole by I-15E and I-15. It appears that initially (in 1963) there were no plans to eliminate any portion of US 395, so it would have continued all the way to San Diego with I-15 ending at I-10 in Colton. The State of California pulled off a major coup in 1972 by having unconstructed state routes 31 and 71 (slated as 6-8 lane freeways) designated as I-15. This meant that the State saved hundreds of millions of dollars by having I-15 transferred from an already existing freeway to almost entirely new alignment. This also meant that the proposed US 395 freeway south of Temecula could also be built with federal, not state dollars by giving it the I-15 designation. Consequently, US 395 no longer served a real purpose and was truncated.

In a decade, the face of signed highways in California changed dramatically. In 1962 there was but a handful of Interstate highways and 23 US highways. In 1972, only eight truncated US highways remained with over 20 Interstate highways either completed or well on their way toward completion. In no other state has there been such a dramatic change in highway numbering and highway types.

The Highways Today

I have traveled over many of the old highways in California and was surprised to find out how much of the old highways still exist. Some of these highways have been easy to find, such as old US 80 in the mountains east of San Diego or US 6, the Sierra Highway north of Los Angeles. In other cases, the old highways have been actually paved over or modified, like old sections of US 99 buried under I-5. Others, such as the old sections of US 99 that go through bypassed towns, have been swallowed up, transformed to match their surroundings. Many more, such as 99W in northern California, have been relegated to the status of frontage road.


As mentioned above, seven US highways still exist in California. These are routes: 6, 50, 95, 97, 101, 199, and 395. Three of them, routes 95, 97 and 199 have remained unchanged while US 6 has been all but eliminated, save for a short stretch between Bishop and the Nevada border. The other three, routes 50, 101, and 395 have more or less been completely transformed into modern superhighways. Old alignments have mostly been bypassed and covered over, just as they had on the Interstates. Essentially, a lot of modern US highways in California bear little resemblance to their forebears and show the evolution of highway building in California. Modern US 101 Shield

The modern style US highway shield, in use since 1956.

The history of US highways is a reflection of the history of 20th Century America. In the 19th Century, the railroads shaped the country, enabling people to travel to and settle in distant places. However, in the invention of the automobile gave everyone unprecedented mobility. The US highway system, itself a reflection of the Progressive Era, shaped the nation by allowing easy access through standardized routes to all parts of the nation.

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