The earliest roads in Texas may have developed from Indian trails or the marked trails of early Spanish explorers, but the first known roads developed as the result of the necessity for travel from Mexico to San Antonio, Goliad, and the East Texas missions. The Old San Antonio Road is perhaps the oldest known highway. Another early highway was the La Bahía Road, and in East Texas Trammel's Trace was a frequently traveled route. The Republic of Texas government approved a Central National Road that aided entry for many immigrants, though it never played the international role that planners originally envisioned. Early Texas law called for the establishment of first-class roads between county seats. These roads were forty-foot-wide cleared paths. Stumps less than eight inches in diameter were cut off at the ground, and larger stumps were rounded off so that wagon wheels could more easily roll over them. Second-class roads were thirty feet wide, and third-class roads were twenty-two feet wide. In 1883 the state government adopted a constitutional amendment that provided for a fifteen-cent county road tax for every dollar valuation. At that time the county commissioners' court had the power to choose routes and construct roads. Citizens could petition for a new road or for improvements to an existing one, after which the court appointed a jury of view to decide on the matter. In nineteenth-century Texas and even into the early twentieth century, water lanes were also important to road development, since they allowed landowners access to the nearest body of water. Work on roads was conducted at the county level. The county commissioners appointed overseers to supervise workers, who were often landowners on the route under construction. Landowners could pay substitutes. Generally, all able-bodied men aged eighteen to forty-five were required to volunteer several days a year for roadwork.
Roads were often named according to their termini-Blanco-San Antonio Road, for instance. Early roads often were mere rocky trails or mud streams. Courses were longer and less efficient as they went around hills, large trees, and boulders. The early roads zigzagged, had right-angle turns, and held water. At the beginning of the twentieth century very few roads in the United States had any kind of hard surface. Probably the most dramatic change in attitude toward highway development in the nation and in Texas occurred with the use of the automobile, which forced drivers to recognize the need for road improvements. In 1903 citizens formed "good roads" associations in Texas in order to promote better roads. The groups organized events like auto tours and set aside special days to do volunteer roadwork. As early as 1903 there were calls to establish a bureau of highways in Texas, but no action was taken at that time. In 1916, however, the Federal Aid Road Act provided for the establishment of state highway departments. That year-the first year of registration-Texas had 194,720 autos registered. The State Highway Department, now known as the Texas Department of Transportation, was established in 1917 by act of the Thirty-fifth Legislature and was originally charged with the primary responsibility of granting financial aid to counties for highway construction and maintenance. In 1921 the Federal Aid Road Act was amended to offer matching federal funds to supplement state money for road building, and Texas counties applied for their share. In 1923 the state imposed a gasoline tax of one cent per gallon, three-fourths of which went to the state highway fund. The Texas Highway Department assumed responsibility for maintaining state highways in 1924, but not until the next year did the department have clear-cut authority for constructing the state highway system.
During the late 1920s the legislature adopted the pay-as-you-go or debt-free concept advocated by Representative Leonard Tillotson of Sealy. The department devised the first statewide marking system in the 1920s, and in 1929 it placed state and federal route signs including mileages and directions on designated highways in Texas . That same year Texas had 18,728 miles of main highways, 9,271 miles of which was hard-surfaced. The period of the 1930s was marked by the Great Depression and the efforts of the department to provide employment through road construction. Planning and constructing a highway involved four principal objectives: safety, convenience, comfort, and aesthetics. Road crews endeavored to shorten routes, smooth dangerous curves and deep culverts, provide adequate drainage, clear weeds and shrubbery to eliminate blind spots, and plant trees, flowers, and shrubbery to help prevent erosion of the road shoulders and beautify the landscape. Greater highway development led to increased mobility and an emerging tourism industry. In preparation for tourists traveling the state for the Texas Centennial the highway department instituted the Office of Landscape Architect in 1933. The purpose of this office was to incorporate both aesthetics and safety into landscaping. The department appointed Mrs. Frank W. Sorrell to lead a Texas citizens' highway-beautification organization to encourage local groups to seek and promote highway improvement in their areas. The department also planned the building of roadside parks. Because of low funds, local groups were encouraged to help by donating time, labor, and supplies. The National Youth Administration provided some federal assistance by constructing roadside parks. Women's groups played a pivotal role in promoting the parks and also lobbied for the restriction of billboard advertising and livestock grazing along highways. In 1936 there were 1,525,579 registered vehicles in Texas, and the state highway system comprised more than 21,000 miles of roads. As the department was emerging from the depression, World War II necessitated a curtailment of road construction because of the scarcity of labor and material.
The most dramatic years in the history of highway development in Texas came after the war. The greatest changes in this period included the development of the farm-to-market and interstate highway systems. As early as 1945 the highway commission authorized the construction of 7,500 miles of rural roads to be financed on a fifty-fifty basis with federal and state funds. The first contracts for construction were let in January 1946 in Randall County. Once the program got started, it became popular, and the demand for rural paved roads grew. The law that really got Texas farmers "out of the mud" was the Colson-Briscoe Act of 1949, which appropriated $15 million a year to the highway department from the Omnibus Tax Clearance Fund to be used in the construction of local roads that did not have sufficient traffic volume to pay for their construction and maintenance. In 1962 the legislature increased the appropriation so that not less than $23 million a year would be available for the construction of new farm roads. In the same year the commission increased the size of the farm-road system from 35,000 to 50,000 miles. By March 31, 1989, the Texas FM system included 41,755 miles of pavement and was the most extensive network of secondary roads in the world. The interstate highway system began in 1956, when Congress established the National System of Interstate and Defense Highways, which was to consist of 41,000 miles linking nearly every major population center in the nation. The system was later expanded to 42,000 miles. The law established a trust fund under which the federal government would pay 90 percent and the states 10 percent of the cost of the system. The states were to pay for the construction and be reimbursed by the federal government. As of March 31, 1989, Texas had completed 3,234 miles of interstate highways, and its share of the system was nearly completed. All routes of the network have been constructed as controlled-access arteries with no stop signs or stop lights and no grade crossings. In some densely populated metropolitan areas the department has also developed high-occupancy vehicle lanes to aid in the flow of traffic. The Texas portion of the interstate system is longer than any other state's.
Private contracting has been an important factor in highway construction in Texas. Texas highways are designed by the department, but the actual construction is performed by private contractors who offer competitive bids. In 1988 some 500 prequalified contractors were bidding on highway-construction contracts in Texas. An additional 500 contractors qualified to do specialty work such as making signs, lights, and signals, offered bids on contracts. As of mid-1989, the department had 901 contracts totaling $3,674,777,952 under way, with 59.55 percent of the construction completed. Generally the Texas Department of Transportation has been able to build and maintain highways more cheaply than the national average. In addition to the farm-to-market and interstate highway, in 1990 Texas also had approximately 12,500 miles of U.S. highways and 14,500 miles of state highways. The entire Texas highway system comprised more than 72,000 miles of highways. Additionally, about 30,000 bridges spanned Texas highways.
Texas highways are financed by revenue from a state gasoline tax, vehicle registration fees, and federal assistance. In 1946 Texas voters approved a good-roads constitutional amendment that provides a guaranteed income for state highways by prohibiting the diversion of receipts from gasoline taxes and vehicle registration to non-highway purposes. The amendment reserved a quarter of the revenues for the Available School Fund and set the remainder aside permanently for state highways. In 1988 voters approved another amendment to ensure that federal funds reimbursing the state for highway work also are dedicated to highway purposes.