By act of Congress, it was established on October 15, 1966, but it was never in play until April 1, 1967.
1966
The US Department of Transportation is headed by the Secretary of Transportation.
The US Department of Transportation is a government department, not a market monopoly
The Transportation Security Administration (TSA) began as part of the Department of Transportation (DOT) but was moved to the Department of Homeland Security (DHS) when that department was created.
The department of transportation
California Department of Transportation was created in 1895.
Arizona Department of Transportation was created in 1974.
Detroit Department of Transportation was created in 1922.
Pennsylvania Department of Transportation was created in 1970.
Oregon Department of Transportation was created in 1913.
The US government has a cabinet-level Department of Transportation. However, most states also have their own Departments of Transportation.
The Department of transportation was created by Congress of the United States. See the quote below. "The Department of Transportation (DOT) was established by an act of Congress, signed into law by President Lyndon B. Johnson on October 15, 1966. Its first secretary, Alan S. Boyd, took office on January 16, 1967. The department's first official day of operation was April 1, 1967."