A huge part of the US economy is the massive network of transportation infrastructure that spans the entire country. On this day, we pay mind to the bodies it took to build the network, the money spent on it, and how much it helps the economy of the country.

The third Friday of May annually has been designated as the federal observance of National Defense Transportation Day.

On May 16, 1957, the United States Congress designated the third Friday of May each year as National Defense Transportation Day.