DALLAS · READING THE ROAD
I-20 opens
in downtown DallasThe drivers arrived first.
Thornton Freeway · April 28, 1966
A flood brought traffic onto Dallas’ new freeway before the ribbon was cut. The road was ready. Teaching people how to drive it had taken a campaign of its own.
Explore the storyTHE CITY
A small distance with a lot to cross
A freeway fitted around downtown
Bridges and ramps crowd the east–west corridor beside downtown buildings. The aerial makes the engineering problem visible: keep the through lanes moving while giving local traffic places to enter and leave.
Photograph: Marvin Bradshaw, as credited in Texas Highways, June 1966.
Selected photographic detail from the second magazine spread. Magazine source
The final link was only 1.8 miles long. It cost $25 million and took three years to build, according to the magazine.
The aerial helps explain that disproportion. Downtown blocks sit close to the pavement, and bridges cross it in quick succession. The article counts 37 bridge structures and 11 entrance and exit ramps. Its widest structure, 260 feet across, carried 19 sets of railroad tracks over the expressway. A short urban freeway had to accommodate a great deal of city. Construction and layout, second spread
“The reason we built the highway (Thornton Freeway) the way we did is because Dallas is built the way it is.”
Collector-distributor lanes carried downtown traffic separately from the main lanes. They gave drivers room to reach local exits without making every entering or leaving car join the through stream. The Dallas Mixmaster photographs show this corridor taking shape before the dedication.
The magazine gave the section a design figure of 125,000 vehicles a day. That was a statement about the traffic it was intended to carry, rather than a count of opening-day use. The space devoted to ramps and separate lanes served that ambition: downtown access had to coexist with large volumes passing through.
THE DRIVER
Teaching Dallas to drive Thornton Freeway
Good engineering still needed a driver who knew which lane to choose.
The Dallas Chamber of Commerce organized a two-week safety campaign, backed by a $6,000 General Motors contribution. Some 400,000 directional brochures went into supermarkets, banks, service stations and hotels. Billboards, posters, radio, animated television spots and newspaper articles repeated the instructions. Public education campaign, first and second scans
“Know your route. Find your sign. Stay in your lane.”
Look at the arrows above the empty pavement. They tell drivers where to place the car before the roads separate. The article also explains an unfamiliar arrangement: left-hand turnoffs could serve right-hand exits. Learning the route beforehand offered an advantage over trying to understand the whole interchange at speed.
Resident Engineer Bob Yielding made the same problem sound simpler during a press tour. Six interchanges made the short section look complicated, he explained, but each driver faced a limited decision at a given exit: take it or continue. The campaign tried to bring that road-level view to people before their first trip.
The dedication photograph shows the Thornton family’s limousine following a police escort. Most motorists would make that trip without an escort. The brochures and signs were meant to make their journeys manageable too.
Find your sign, then your lane
The overhead signs distinguish I-20 east and US 80 from US 67 north and the US 75 / Harwood Street / Central Expressway exit. Route numbers, arrows and an advance exit sign turn the complicated interchange into decisions a driver can make from the pavement.
Photograph courtesy Dallas Chamber of Commerce, as credited in Texas Highways, June 1966.
Selected photographic detail from the third magazine spread. Magazine source
THE NUMBER
The I-20 signs belong to today’s I-30 corridor
That I-20 shield is a useful clue to the photograph’s age.
This opening was on the east–west freeway beside downtown Dallas. Today’s southern I-20 bypass is a different corridor. TxDOT’s designation files record I-20’s relocation in December 1971 and I-30’s extension westward over the former I-20 route and the Dallas–Fort Worth toll road. These are designation actions, not dates when every bypass section opened. TxDOT’s route records
The numbers changed, but the photographs preserve the task facing Dallas in 1966: fit a freeway into a working city, drain it during a storm and help drivers choose the right lane. The last part was important enough to print 400,000 brochures.
ROAD AND RECORD
A route number can change.
The final downtown Thornton Freeway section opens on April 28, signed I-20.
December 2 designation actions relocate I-20 and extend I-30 over its former route.
Sources: June 1966 magazine; TxDOT designation files.
FOLLOW THE EVIDENCE
Sources & further reading
The new commentary uses all three surviving scans of “A Vital Link for Dallas,” with three photographic details selected to examine the ceremony, downtown engineering and lane guidance. The complete scans remain available below and in the viewer.
- Texas Highways, “A Vital Link for Dallas,” June 1966. Opening page and two following spreads; the final printed folio is 7. The scans do not establish an article byline. Original scans: opening page · second spread · third spread.
Return to: opening account · engineering · driver education · ribbon detail · aerial detail · sign detail.
- Willard B. Mills and Elmer E. Schroeder, USGS: Floods of April 28, 1966 in the northern part of Dallas, Texas, Water-Supply Paper 1870-B, 1969. The publication’s abstract supports the flood’s severity, deaths and antecedent saturation; the full report was not used for the freeway opening account.
- TxDOT Highway Designation Files: Interstate Highway No. 20 and Interstate Highway No. 30. Minute Order 065684, December 2, 1971, and Administrative Circular 125-71 document the route changes.
About this article: TexasFreeway presents selected historical images for commentary, analysis and education under fair use. Images remain credited to their respective sources. Their inclusion here does not grant permission for reuse elsewhere.
Online supporting sources checked October 3, 2026. The source issue date describes the historical magazine, not the preparation date of this commentary.
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THE FLOOD
Dallas motorists opened the road first
On April 28, 1966, Dallas had a freeway dedication scheduled. The weather supplied a much more urgent reason to open the road.
The June Texas Highways account describes flooded streets, power failures and hundreds of people driven from their homes. North-side commuters crowded onto Central Expressway and Thornton Freeway. Some bypassed the barricades on the final downtown section; police then obtained District Engineer Luther DeBerry’s permission to remove them. The magazine’s opening account
This was a serious flood, beyond the disruption of a ceremony. A later U.S. Geological Survey investigation recorded at least seven deaths directly caused by floodwaters in northern Dallas and described ground already saturated by earlier rain. USGS flood investigation
The magazine says the new freeway’s drainage system withstood the rain. Its opening nevertheless depended on a practical decision above ground: let people use the finished pavement. Later, Mrs. R. L. Thornton cut the ribbon. The planned 1903 Oldsmobile appearance had been lost to the same heavy rains.
The ribbon came after the traffic
Mrs. R. L. Thornton cuts the ribbon held by Earl Hayes and Mayor Eric Jonsson. The formal ceremony gave the opening a public face, even though motorists had already put the new road to use that morning.
Source: Texas Highways, June 1966. Photographer not identified in the scan.
Selected photographic detail from the opening magazine page. Magazine source