Texas opened the country's fastest highway, a stretch of toll road from Austin to San Antonio, in 2012..

While U.S. motorists don’t have an Autobahn, with its lack of speed limits, there’s been a significant increase in the allowable pace in much of the country since the national 55 mph restriction was lifted nearly two decades ago.

Despite the objections of safety advocates, Texas now has both the single fastest highway in the country — a toll road with an 85 mph speed limit – as well as the fastest average allowable speeds when you factor in all its various limited-access roads. Those drivers looking to get somewhere fast might steer clear of the District of Columbia and Alaska, however, the two states having the nation’s lowest top and average speeds, according to a new study by the Governors Highway Safety Association, or GHSA.

Those two states have become the exception, rather than the rule, more and more allowing drivers to put the pedal to the metal. In fact, four states now have top speeds of at least 80 mph, with another dozen pushing their limits up to 75.

It’s been four decades since the first Mideast oil shock rattled the nation, fuel prices soaring while supplies dried up. Under then-President Richard Nixon, Congress enacted a national 50 mph speed limit intended to conserve scarce fuel – and improve highway safety at a time when nearly 50,000 Americans were killed in motor vehicle accidents annually.

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Facing pressure from the public – notably including long-haul truckers who argued the draconian regulations were leading to higher shipping costs – Washington raised the limit, just slightly, to 55. The “double-nickel” remained in place until the mid-1990s, when Congress began to remove the regulations. At first, states were allowed to increase speeds only on the Interstate system but, eventually, power to set limits was turned over to the states entirely.

And they’ve been raising them ever since.

For the most part, the biggest jumps have also occurred in the nation’s largest states. Perhaps it should be no surprise that Texas now has the highest limits, however you measure them. That includes a 91-mile stretch of State Highway 130 between the capital of Austin and San Antonio where motorists now can top out at 85 mph – if they’re willing to pay the toll.

Factoring in all of the Lone Star States Interstates, state freeways and toll roads, as well as other limited access highways, the GHSA came up with an average Texas highway speed of 78.3 mph, about 1.6 mph faster than second-place Idaho, at a still swift 76.7 mph.

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A quick look at the data shows that speed limits in the Midwest and Southwest run faster than the rest of the country. Along with Texas and Idaho, Utah and Wyoming also have set top speeds of at least 80 mph. Montana – which once had no official speed limit – Montana, New Mexico, Oklahoma and Nevada are among those states with speed limits of 75 mph.

The lone East Coast state on that list is large and sparsely populated Maine.

Alaska, meanwhile, is the exception among big states, with a speed limit of only 55 mph, the same as small and densely populated Washington, D.C., notes the GHSA, which represents state highway safety departments.

Even along the East Coast, there’s been a grudging trend towards faster speed limits. Delaware now averages 58 mph, the same as New York and Rhode Island.

Indeed, despite a roughly 40% decline in highway fatalities since the original 50 mph limit was passed – deaths declining even in recent years when speed limits were raised – regulators and safety groups remain unconvinced. The National Highway Traffic Safety Administration earlier this year listed speeding among the three most significant causes of deaths and serious injuries. And a statement from the Insurance Institute for Highway Safety asserted that, “the research is clear that when speed limits go up, fatalities go up.”

Perhaps, but the trend to faster roadways appears to be far from finished. Idaho only joined the 80 mph club in July after a study demanded by worried safety advocates. Whether any other states will eventually catch up to Texas remains to be seen.

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