The Blitzen-Benz was purpose built to do just one thing, to break speed records (not racing), and it did repeatedly from 1909 through 1911.
Its speed of 228.1km/h (141.73mph) on April 23rd, 1911, driven by Bob Burman at Daytona Beach, stood as a record until 1919. Twice the speed of the fastest airplane, (12 April, 1911, Alfred Leblanc @ 69.442mph/111.801kph in a Blériot Blériot) and even shattering the record speed of 210km/h set by a locomotive in 1903. This record was not even officially broken in an airplane until 1920!
Of the six originally built, this is one of only two that exist today, and is displayed at the Mercedes-Benz Museum in Stuttgart, Germany.