In 1956, Congress approved the Federal Highway Act, which allocated more than $25 billion dollars to build 41,000 miles of public highway, crisscrossing and uniting the Continental United States in an entirely new way. The first transcontinental road, from Washington D.C. to San Francisco, was built by the US Army in 1919, though the nation had very limited potential for expanding or even maintaining its existing infrastructure until the 1950s.